►This site was originally created for my kids and their cousins, because we did science together. We eventually added more friends and I ended up having science classes for five years. I am no longer adding to the site (since 2014), but will leave it up for others' use. I do post to facebook occasionally if I come across something to share. =)

►Please accept my apology for any broken links or videos that do not work. I am always disappointed when people take down their videos from YouTube. It makes it hard to find just the right replacement. And because the videos were posted years ago, I usually have no recollection of what the video was about.
I kept thinking I would have time after my kids graduated, but life has filled up my free time with new responsibilities. =)

►Please do not email, asking me to post your website link, or to review something to put on my site. Any resources posted on this site are things I had found on my own during my regular searching for material I needed at the time, and liked it well enough to post here. There have never been any affiliates on my site, and as it is no longer active, would not be worthwhile at this point. ;)
Thank you!

Secret Messages! Disappearing Ink!

You can also apply heat from another source, such as a toaster.
►Read more here about how this works and how to get the ink to reappear.

Apologia General Science, Module 8, Uniformitarianism and Catastrophism

What we did at Sahm-I-Am

Quizlet M8

Try a Bite of Trilobite! (I used Pepperidge Farm lemon cookies)
Trilobite Model - print on cardstock

(1)  p. 189-194, Uniformitarianism and the Geological Record
Those who believe in uniformitarianism believe this is how to get the geological column.

How Uniformitarianists view Index Fossils

The truth about the geological column  =)


(2)  p. 195-197, Uniformitarianism and Evolution


(3) p. 197b-202, Catastrophism and the Geological Record
Mt. St. Helens - examples of stratified layers in short spans of time, not millions of years.


(4)  p. 202b-206, Catastrophism and the Fossil Record


(5) p. 206-210a, Uniformitarianism or Catastrophism: Which is Better?
trilobite, coelacanth (SEE-luh-canth)


(6) p. 210-213, Evolution: Another Weakness of Uniformitarianism

Expelled: No Intelligence Allowed

This is available on Netflix, on DVD and Blue-ray.

But I also just discovered it on youtube.:)
It was on a user's channel and was out of order, so I saved them here. 

Info from Netflix:
2008, PG, 95 minutes
Hosted by Ben Stein, this controversial documentary examines how pro-intelligent design scholars and scientists are often chastised, fired or denied tenured positions by those who believe in Darwin's theory of evolution. Nathan Frankowski's film explores how scientists who believe in God are oppressed and how the acceptance of Darwinism might have played a role in the formation of the Nazi regime.

Apologia General Science, Module 7, The Fossil Record

What we did at Sahm-I-Am

Quizlet M7
• Look through these pictures to review types of fossils.

Petrified Paper
Three-Dimensional Geology
See these and more at Debbie's Educator's Resources.  (Thanks, Debbie!)
Homemade playdough for exp. 7.1 (video)
Example of making fossils for exp. 7.1 (video)
Leaf Impressions (model for carbon remains or impressions)

(1) p. 161-163, The Making of Fossils Part 1:  Casts and Molds
You may know what a jello mold is, or if you've ever played with play-do, you may have pressed it into a mold.
The mold is like the hollow imprint that you pour the jello into or press the play-do into.
A cast is the result you get from something being poured in, creating a copy of the shape of the mold.
Learn about real-life molds and casts.

►How molds and casts are sometimes made.  Part 1, Part 2


(2) p. 164-165, The Making of Fossils Part 2:  Petrifaction


(3) p. 165b-166, The Making of Fossils Part 3:  Carbonate Residues and Impressions
I can find no videos for this, so here are a few pictures


(4) p. 167-170, The Making of Fossils Part 4:  Avoiding Decomposition
Insects and other small animals can be trapped in amber, a kind of resin that is a sticky sap that hardens when exposed to air.
You will see that these amber-encased insects in this video are labeled as millions of years old.  However, we believe in a young earth - about 6,000 years old.

If insects trapped in amber WERE millions of years old, this would be evidence of NO evolution, since the "million" year old insects look just like today's insects.

If all living organisms descended from the same primitive life form, then the rock strata of the earth should be filled with the fossilized remains of animals that were once part of a great evolutionary chain.  There should be fossils in multiple stages of evolution.
The "missing links" are non-existent.


(5) p. 170-175, Three General Features of the Fossil Record

1.  Most fossils are found in sedimentary rock.  Since most sedimentary rock is laid down by water, it follows that most fossils were laid down by water as well.
Igneous rock is formed from magma, and most creatures trapped in magma are most likely to be burned up, so it isn't common to have fossils in igneous rock.
2.  Nearly 95% of all fossils on this planet are the fossils of clams and other hard-shelled organisms.  Most of the remaining fossils are of either water-dwelling creatures or insects.  Only a tiny fraction of the fossils we find are of plants, reptiles, birds, and mammals.
3.  The fossil record contains the remains of some plants and animals which are still living today.  Some of the fossils we find are of plants and animals which are now extinct.


(6) p. 175b-176, A Fourth General Feature of the Fossil Record

4.  The fossils found in one layer of stratified rock can be considerably different than the fossils found in another layer of the same stratified rock.

Trilobite images

The most common trilobite fossils are cast fossils.
They are found in the Grand Canyon's layers above the Great Unconformity.  Fossils of worms are found in the three strata directly above the Great Unconformity, and fossils of common fish we see today are found in the the top layer.
The answer to why these different types of fossils are in different strata is found in comparing catastrophism and uniformitarianism.

►See some trilobite molds and casts.

► Look through these pictures to review types of fossils from this module.


(7) p. 176-179, Geology and Paleontology from the Uniformitarian Viewpoint
The assumption of uniformitarianism is best summed up with the phrase, "The present is the key to the past."  In other words, uniformitarianists assume that how things are occurring today are how they have always happened.  The "uniform" in the word implies something stays the same.
There are many instances of local destructive floods that show that strata is indeed laid down by water.  Some instances are large-scale, however not as large as what the Flood caused in the Grand Canyon.  But they are great examples that geography can undergo vast changes in a short period of time.  We wouldn't want the Flood to happen again of course!  And in Genesis 9:11, God promised it wouldn't.


(8) p. 179-182, Geology and Paleontology from the Catastrophist Viewpoint
If rivers carve out huge canyons over millions of years, and if the earth were billions of years old, then every river, stream, and creek should be a Grand Canyon by now.

Interactive Thanksgiving Site

Interactive Thanksgiving Site at Scholastic.
Click to hear things read aloud throughout the site, click to take the journey (reads aloud automatically), or tour the ship, see the slideshow, click on the timeline and it will read aloud, etc.  Just about everything can be clicked on to the read aloud.
This is an awesome site, and your kids can spend several hours here.  =)

Find the Hidden Colors of Autumn Leaves

Just found this link and I'm saving it for when we do Biology again.  Posting for whoever needs it now.  =)
Find the Hidden Colors of Autumn Leaves.  
Looks pretty neat!  =)

Candy Experiments!

Came across this link this morning.
Candy Experiments.
I want to try the skittles one!  =)

Apologia General Science, Module 6, Foundations of Geology

What we did at Sahm-I-Am

Quizlet M6
• Online practice quiz
• How are materials from the earth broken down?
-Click on a scene at the top.
-Click on Hear below the larger image.
-Click on the water or oxidation symbols at the bottom to see how these cause erosion.
• How do glaciers shape the land?
-Click on one of the two tabs at the top, then click on the labels to learn about the landforms.
-At the bottom, look at the Site that is shown, and figure out which landform it is.
-Use the Clue if you need it.  Check your answer.
-Scroll down and choose another Site.

Petrified paper
Weathering and Erosion - lots of links!  I love the 12 stations; we're doing some of those.
Stations worksheets - I typed up my own using these for an example.
Teacher-Friendly Guide to Geology.  Nice guides for educators based on your area of the country.  See the left sidebar.
• Some good pages found here under "Geology"
See these and more at Debbie's Educator's Resources.  (Thanks, Debbie!)

(1)  p. 137-138 Introduction
Uniformitarianism and Catastrophism


(2)  p. 138b-142a, Soil, Rocks, and Minerals
The top layer of soil is rich in humus.  Humus is the decayed remains of once-living creatures, and contains nutrients that plants use.
Other components of most soil are gravel, sand, silt, and clay.

This tells how to determine if soil is good for growing things - if the soil is a "loam," which you don't need to know yet, but still a good video about the different components of soil.

Way beneath the dirt of the earth's crust is a solid layer of rock.
There are three main kinds of rocks:  sedimentary rock, igneous rock, and metamorphic rock.

  • Igneous rock is formed from magma (molten rock deep in the earth).  Sometimes the magma cools inside the earth, and other times it erupts from volcanoes.  
  • Sedimentary rock is formed from particles of shells, or sand and pebbles weathered from igneous rock.  Together, these particles are called sediment.  When the sediment accumulates in layers over time, they harden into sedimentary rock. You can see the sediments in the rock. 
  • Metamorphic rock is formed from igneous rock and/or sedimentary rock under the surface of the earth due to high heat and pressure, but not hot enough to melt.  If metamorphic rock gets hot enough to melt, it becomes igneous rock.  
These rocks form from one another in the rock cycle.

From ingeous rock, to sedimentary rock, to metamorphic rock.

There are different types of igneous, sedimentary, and metamorphic rocks.
The Rock Song!  ♪♫  
(Remember to be gneiss, lol!)

What kinds of rocks are found where you live?

Minerals are inorganic.  This means they didn't come from a once-living being.  Minerals are crystalline substances found naturally in the earth.
A crystalline substance has a sharp, geometric shape.  It doesn't have rounded edges like most rocks you see.  These sharp-edged minerals are what make up rocks.

Great video showing many types of minerals.  I love the "peacock ore" at 5:30 -- So pretty!!!
Some have been through a rock tumbler and are now smooth.


(3) p. 142-145, Strata in Sedimentary Rock

Arial view of the Grand Canyon. Beautiful!!!


(4) p. 145b-149, Weathering of Rocks
Weathering is the breakdown of rocks, soils, and minerals into sediment by the forces of nature.
►Look at these awesome pictures of weathering.

There are two types of weathering:
  • chemical weathering from acid rain or rust
  • physical weathering from wind or water carrying sediment that wears away at rocks and shorelines, or from extreme heat or cold, or from plant roots that break up sidewalks or pavement, etc.
However, both types of weathering occur in place.
►Once the sediment moves away from its location, then it is called erosion.
(Please ignore the reference to billions of years.  sigh.)
This video is actually about both weathering and erosion.


(5) 149b-154a, Erosion
Erosion is displacement of rock fragments, sediments, soil, and other particles that are carried away by wind, rain, or ice.

Rivers carry along sediment and deposit it into a larger body of water such as a lake or more commonly, the ocean.
River erosion.

"A delta is a landform that is formed at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river. Over long periods of time, this deposition builds the characteristic geographic pattern of a river delta."

A delta gradually grows further out into the ocean (or lake, etc.) while at the same time builds up so that part of it is above water.  Plant life can grow here.  The main river will cut through this body in several branches and continues to the ocean.  On this picture of the Nile Delta, you can see the delta extended into points at those areas.

Caverns are another kind of erosion.  It is common for the different "rooms" in caverns to be named for their appearance.

Yay for bats!  =)


(6)  p. 154-156, Bringing it all Together:  The Basic Structure of the Grand Canyon

►More about the Grand Canyon at Answers in Genesis.

An unconformity is a surface of erosion that separates one rock layer from another.  In other words, the layers are not totally level because one has eroded a little before more sediment was laid down.  It did not conform to regular layering.

Various unconformities in order of the video:
  1. A disconformity occurs where there are parallel, stratified rock layers above and below a disconformity, but there is erosion between them.
  2. An angular conformity is at an angle, with more layers on top if it.  The Great Unconformity is an angular connformity in the Grand Canyon.
  3. A nonconformity  is when stratified layers rest on top of unstratified layers, such as the separation of metamorphic or igneous rock and the first layer of sedimentary rock on top of it. (Nonconformity isn't labeled in your book, but it is there at the bottom of the picture.)
  4. Paraconformities will be discussed in Module 8.
An intrusion forms when magma from under the sedimentary rock is injected into the cracks of the sedimentary rock.  It hardens into a "vein" of igneous rock.
Intrusions that run parallel to the sedimentary layers are called sills (horizontal like a window sill).
Intrusions that run perpendicular to the sedimentary layers are called dikes.  Perpendicular lines form a kind of T to each other.

The lower layers were indeed laid down before upper ones, but that does not mean it took millions or billions of years.  It shows the relative age - how they are related shows that one is older than another, but not by how much.
Remember, there is nothing between the layers to indicate great amounts of time had passed.  No plants that grew, not enough weathering, etc.

1:50 - nonconformity on top of intrusive igneous rock.
3:05 - disconformity
3:48 - angular conformity
4:25 - intrusion

FREE Sign Language Lessons

Copyright © Dr. Bill Vicars, sign language resources at Lifeprint.com

Learn American Sign Language for free at American Sign Language University at Lifeprint.com.
There are 30 free lessons that are meant to cover 2 semesters for 1 full credit.
(The page at the ↑ above Lesson link shows the lesson links 1-30, then at the bottom shows the same lessons broken down by semester and unit.)
Each lesson has Objectives listed at the top with links to other learning resources.  Each lesson has videoed vocabulary, sentences, and sometimes a videoed "story."

The links below are from various places on the site, and you'll come across some from within the actual lessons.  I put them here in one place for easy reference.

► Practice Quizzes for each Lesson
► Quizzes and Cumulative Tests
► An additional Quiz for Lesson 1
► ASL Dictionary (at the top, you can also click on Phrases for all the sentences for each lesson, or click on Advanced.)

► Multiple fingerspelling charts, some with no letters written in for the purpose of practicing.
► Alphabet - hover your mouse over a letter
► Interactive Fingerspelling Practice Quizzes
► Printable wordsearch "Fingerseeks"
 Fingerspelling Practice Watch the word spelled and type in your answer.  Choose speed and # of letters.  Scroll down and choose from different categories.
► Article: Lexicalized Fingerspelling

► Numbers and tips for signing numbers, plus video for numbers 1-50.
Numbers Practice Watch the number signed and type in your answer.  Choose speed and number range.

Lifeprint.com - the online chats that started it all, discussion among online students.

►Another sign language site is ASL Pro.  It looks like it would be a good reference site.  I like the Conversational Phrases.  =)

Apologia General Science, Module 5, The History of Life: Archaeology, Geology, and Paleontology

What we did at Sahm-I-Am

Quizlet M5

• Tree-Ring Dating Lesson Page (I used the lesson part only)
Tree-Ring Science (student page)
Flood Legends
See these and more at Debbie's Educator's Resources.  (Thanks, Debbie!)

(1) p. 111-112a, How Do We Learn About the History of Life

Archaeology - the study of past human life as revealed by preserved relics.

Geology - the study of earth's history as revealed in the rocks that make up the earth.

Paleontology - the study of life's history as revealed in the preserved remains of once-living plants and animals.


(2) p. 112-116, Archaeology and History

There are three tests to evaluate historical documents:
  1. The internal test evaluates whether or not the document contradicts itself.
  2. The external test checks whether or not the document being examined contradicts any other known historical or archaeological facts.
  3. The bibliographic test is the most important and makes sure the document is essentially the same as the original.
    To do this, this test requires 1st- or 2nd-hand reports based on eyewitness accounts.
    Two other important factors are (1) how many different copies are made by many different people, further clarifying that the copies were accurate, and (2) if the copies were made not too many years after the original.  The shorter the time period, the more reliable.
When using the internal test, we must always apply Aristotle's dictum because what seems to be a contradiction might not be a contradiction due to difficulties in translation.
Any unverified inconsistencies must be examined, taking into account that language and its use changes over time.
Aristotle's dictum:  The benefit of the doubt is to be given to the [historical] document itself; not assigned by the critic to himself.

Here is an example of how the English language has changed.  This example is only from about 600 years ago!
Brace yourself - you'll either cringe or laugh!  =D


For the next several sections, I could find no videos.
I did give brief descriptions above of the three tests applied to historical documents, but that is all.  =)


(3) p. 124-128, Archaeology in the Absence of Historical Documents

Dendrochronology - study of tree rings to determine the age of a tree

Dendrochronology is not a completely accurate way of dating artifacts; the calculated age from a dating method such as dendrochronology is called an absolute age.
An absolute age is not absolute, however -- it just means that through calculations, an age has been assigned to the item being studied.
A known age is much more accurate, and in archaeology, is the only one that is certain.
  • Known age – the age is determined by a date printed on it (ex. on a coin) or a reference to the artifact in an authentic work of history (like a tomb or king was referenced in a document)Very few artifacts have known ages.
  • Absolute age – the calculated age of an artifact from a specific dating method [such as dendrochronology] that is used to determine when the artifact was made.Absolute ages are dates that are assigned to an artifact or document.  Absolute age does not mean it is totally correct.  It is a close estimate.
The only ages that are certain in archaeology are the KNOWN AGES.

Ages determined by dendrochronology [dendrochronology ages are absolute ages] are upper limits for the age of an artifact.  In other words, that is the oldest it could possibly be, but it might be younger. 
Sometimes trees have 2 rings in one year, so dendrochronology shows the oldest that the tree could be, or the oldest that the artifact associated with the wood could be.
Examples of artifacts that may be studied are old ships, Pilgrim dwellings, a Navajo canoe.

An absolute age is a close estimate, and in the case of dendrochronology, it is generally a high estimate.  It can’t be a low estimate, because a tree will not ever skip growing a tree ring that year.

Radiometric dating (also called Carbon-14 dating) is using a radioactive process to determine the age of an artifact.  This method is used on fossils (dinosaurs, etc), and is very unreliable.
IF the item is less than 3,000 years old, it is a little more reliable – about like dendrochronology – approximate, but not certain.
Radioactive/Carbon-14 dating gives an absolute age, which means a date has been assigned, but it is not  KNOWN AGE, which is the only age in archaeology that is certain.

Wow!  A huge dendrochronology laboratory!

►Dendrochronology testing of Doucet Hennessy House in Bathurst, New Brunswick
►Sometimes narrow rings do not indicate dry weather, but a crowded forest.  Video 1, Video 2
Learn more.  Intro to dendrochronology with Tom Windes (rhymes with kinds)
Learn a lot more with Tom Windes (Parts 1-8 total around 40 minutes)


(4)  p. 129-131, Relative Dating and the Principle of Superposition; What Do We Know about Human History?

It's fairly simple - the Principle of Superposition - but not necessarily true.

If you made a layer cake, and you have 5 layers of yellow cake, and each layer had creamy chocolate frosting in between, you can know when the layers were put there.
But you cannot tell whether the cake or the frosting was made first.

The Principle of Superposition says that when artifacts are found in rock or earth that is layered, the deeper layers were laid down first, and hold the older artifacts.  This is not necessarily true.  
When Noah’s Flood occurred, a lot of earth, rocks, bones, fossils, etc, were mixed together. 
If you have a jar with rocks, sand, and fine dirt in it, and mix it all up with water, the rocks will settle first, then the sand, then the dirt.
After the Flood, all this stuff had to settle back down, and it did so in layers called strata.  (Strata starts with the same letters as stripe, so that may help you remember it.)
Archaeologists often assume that layers are formed one at a time, over millions of years.
Layers can form one after the other as in the case of volcanic ash, but to say that all the artifacts found all over the world in the different layers were put there in order is false.

Archaeologists often get the relative age by using the Principle of Superposition.
The term "relative" means how something is positioned related to something else.

If I was in the audience and saw you standing on a platform, I might say you were on the left of the platform.
But you might say you were on the right of the platform.
Where we each say you were standing is relative to where we are ourselves.

If I laid a book on the table and asked you if it was moving, you would say no.
But if I asked an astronaut on the moon, he would say yes.

So because of the relativity of the layers, archaeologists often assume they were put there over time, and not simultaneously.  Many times artifacts are said to be millions of years old because they actually sank first with the more dense layers of sediment after the world-wide Flood.

"This law only applies to the rocks if they have not been scrambled up; if they have not been 'unconformed'."
But they have been scrambled up - by The Flood.  =)

No time-gap between the layers such as wind erosion, or plant life.

Did the Colorado River flow uphill?

Ark Hunter, Jeremy Wiles, joins Eric Hovind and Paul Taylor to discuss stories gathered from around the world while on a journey to find evidence of Noah's Ark.
(Jump up to about 3:55, and skip both commercials - about 1 min. each.)

Some interesting points:
If it was only a local flood, why build a boat?  Why not just go elsewhere during the flood?
How would anyone have had knowledge or even time to build a large boat in advance?
Why have birds onto the ark if it was only a local flood?
There are so many stories of the Flood all over the world!

Apologia General Science, Module 4, Science, Applied Science, and Technology

What we did at Sahm-I-Am

Interactive Study Links:
• Quizlet
• Simple and Complex Machines - interactive, just for fun.  =)
• Edheads: Simple Machines - interactive, just for fun.  For simple machines, hover over the house.
• See the Inventor's Toolbox for examples of Simple Machines, then go to Gadget Anatomy to test what you learned.

• Edheads: Simple Machines
• Penny Lever lab, etc.
• Wheel and Axle
• A Screw is a kind of Inclined Plane (worksheet)
• Lever, Wheel and Axle, Pulley
• Six Simple Machines (I like the popcorn one on p. 5!)
• See these and more at Debbie's Educator's Resources  (Thanks, Debbie!)


(1)  p. 83-86a, The Distinction Between Science, Applied Science, and Technology

►Science attempts to understand how the universe and everything in it works, and how it is all interconnected.
Science is motivated by curiosity.  The goal of science is knowledge.

►Applied science takes that knowledge and applies it to improve or simplify our lives.  In other words, take the knowledge and do something useful with it.
The goal of applied science is to find a way to make something easier.

►Technology is the invention that makes things more simple or easier.
The goal of technology is to use the applied science to actually make a product that will make something more simple or easier.
Technology is not always a machine.  Technology is "any invention or process that makes life better or a job easier." -Apologia General Science, p. 84

If you do an experiment and learn something from it, that is science.
If you find a way to make something better or easier, you have applied that science.
If you actually invent something to make life better or a job easier, that is technology.


(2)  p. 86-92, Simple MachinesThe Lever

Effort is the force used to push or pull.
Load or resistance is what is being lifted or pulled.
Fulcrum is the point at where there is a hinge-like motion.
►See this picture

Read More about Simple Machines
Understanding Simple Machines

By using any simple machine to increase force or motion, you have an advantage called a mechanical advantage (or MA).  This mechanical advantage can be measured

Formula for finding the Mechanical Advantage of a Lever:
MA = (distance from fulcrum to effort) ÷ (distance from fulcrum to resistance/load)
We used the term "fe-fr" to help us remember the order.
If you look at the image of the three classes below, you will see it can take a bit of brain work to think how to apply this formula to each of these different levers.

1st class, 2nd class, and 3rd class levers
Remember FLE (or FRE):
F(orce) in the middle = 1st class
L(oad) or R(esistance) in the middle = 2nd class
E(ffort) in the middle = 3rd class

►Classes of levers animations


(3)  p. 93-95, The Wheel and Axle
Formula for finding the Mechanical Advantage of the Wheel and Axle:
MA = (diameter of the wheel) ÷ (diameter of the axle)


(4)  p. 95b-99, The Pulley
Formula for finding the Mechanical Advantage of Pulleys:
MA = count the number of pulleys!  =)
Unless there is only one pulley -- then there is NO mechanical advantage because all you did was change the direction of the pull.

And that is why, on a 20-speed bicycle for example, you have to pedal faster than on a single-speed bike (with one gear).  When the force exerted is easier, the distance will be greater.  Your pedals have to move a greater distance.  On a single-speed bicycle, you have to exert more force, but do not need to pedal as fast.


(5)  p. 99b-100, The Inclined Plane
Formula for finding the Mechanical Advantage of an Inclined Plane:
MA = (length of the slope) ÷ (height)
(This is the same as the formula for the wedge)


(6)  p. 100b-102a, The Wedge
Formula for finding the Mechanical Advantage of a Wedge:
MA = (length of the slope) ÷ (height)
(This is the same as the formula for the Inclined Plane)

I couldn't find any useful videos for the wedge.  So if you
know of any, please let me know!  =)

A wedge may look like an inclined plane, but it is used differently.
►"An inclined plane is meant to ease the force required to lift a load."
[Something moves over the surface of an inclined plane.]
►"A wedge... magnifies the force that is being applied." Apologia General Science, p. 101
[A wedge moves through something.]

Most common is the wedge used to split wood.  This is a double wedge -- two wedges put together.
Sometimes splitting wood with an axe is not quite enough.  A splitting wedge can be placed on the upended wood and a sledge hammer used to force the wedge into the wood.
Here is how one man used a tire to help him!  Click over to about 3:00 minutes.

My husband who likes to play golf uses a pitching wedge.
You can also wedge open a door with a door wedge.

Some wedges are not used as a simple machine:
You girls may sometimes wear wedge shoes.
You might eat a wedge of cheese or a salad wedge.
If you want to sit between your two best friends, you can wedge in between them.  This can be very useful, but I would not call it a simple machine.  =)


(7) p. 102-105, The Screw

Formula for finding the Mechanical Advantage of a Screw:
First find the Circumference of the screwdriver or device turning the screw:
1.  Circumference = 3.1416 x (diameter) [note: this is the only multiplication in the formulas in this module.]

Plug the circumference into your MA formula:
2.  MA = (circumference) ÷ (pitch)  "Pitch" is the distance between threads on the screw.

Apologia General Science, Module 3, How to Analyze and Interpret Experiments

What we did at Sahm-I-Am

• Quizlet M3

Thinking Objectively
See this and more at Debbie's Educator's Resources.  (Thanks, Debbie!)

(1) p. 58-63a, Experiments and Variables
Independent variables vs. dependent variables.
An independent variable is what you decide.
A dependent variable depends on what you decided.
In Exp. 1.1, A Floating Egg, it was decided how much salt should be put into the water.
That was the independent variable.
What happened to the egg was the dependent variable.
The more the independent variable (amount of salt) changed, the more the dependent variable (how much the egg floated) changed.

It is important to note that some variables do not affect the experiment enough to really count.
However, you should always reduce as many variables as possible that are not necessary for the experiment.
Another thing to keep in mind is to only change ONE variable at a time.
(Remember my daughter's computer screen.)
In the egg experiment, you changed the amount of salt, but you did not increase or decrease the amount of water, or the size of the egg, or the glass.
Some of these variables would obviously change the experiment more than others, such as an increase in the amount of water could reduce the salt-to-water ratio.

Reducing the number of variables - you should only have one experimental variable.  Everything else should be the same.

Part 1

Part 2


(2) p. 63b-69, Using a Series of Experiments
In this section, we did a series of experiments to show that soap decreases the surface tension of water.
We also learned about the importance of having a control for your experiment.  A control is the variable or part of the experiment to which all others can be compared.  Simply put, a control is the variable in which nothing is changed.  It was the part that had no experimental treatment.

Surface Tension - 36 drops of water on a penny

Surface Tension

Another thing that could be done instead of tipping the screen-covered jar, is to spray some soapy water onto the screen.  Soap molecules interfere with water's surface tension.

What does soap do?

Review:  Controlling variables - making sure everything is the same except for the variable being tested.


(3) p. 70-73a, Recognizing Experimental Variables When They are not Obvious

The Scientific Method (with a funny video clip), and Recognizing Variables
control is the variable or part of the experiment to which all others can be compared.  It is the part that receives no experimental treatment.
placebo is a fake pill that contains no medication.
►You can see the funny part again here.  =)

Control groups and Blind Studies


(4) p. 73-76, Interpreting the Results of Experiments
Which type of graph to use?

Line and bar graphs are done in the 1st quadrant so that you only see ¼ of  a whole graph.
(See image.)
The Independent Variable (what you decide) goes on the bottom on the x axis.  It will increase in even increments, and you mark those across the bottom.
The Dependent Variable (what changes) goes on the left on the y axis, and again, should be marked in increments.  The results will vary, going up or down.

In this line graph, the independent variable is indeed on the bottom with the dependent variable on the left.
You can see that the independent variable, time, is on the bottom.  The increment of time was decided by the person doing the experiment.

See the first bar graph here.
Patients were then given either a real medication or a placebo.
The dependent variable, the results, are written in increments on the left of the graph so you can see these results at a glance by how far the bar extends upwards or how far up or down the line is graphed.

Apologia General Science, Module 2, Scientific Inquiry

What we did at Sahm-I-Am

Students, Practice these frequently:
• Quizlet M2

D&T Activity (my kids loved this)
D&T Activity worksheet
Scientific Method in Action
See these and more at Debbie's Educator's Resources.  (Thanks, Debbie!)

(1) p. 35-39, What Science is NOT
A couple of experiments in your book demonstrate that objects do fall at the same rate.
If there is air resistance this interferes and slows down certain objects, but doesn't change the fact that lighter objects with no air resistance do fall at the same rate as heavy objects.
One thing that is not mentioned in this module is that objects will fall at an accelerating rate (getting faster).  This continues until the object(s) reach a point that the downward pull of gravity is equal to the upward push of air resistance.  Objects with more air resistance will fall slower than other objects.

The Feather and the Coin (in a vacuum -- no air)

Hammer vs. Feather - Apollo 15 on the moon!

From experiment 2.1 in your book, it may seem as if one could prove that heavy objects fall faster than lighter objects.  But experiment 2.2 was a counter-example to show that the first experiment was faulty.  The results of the first experiment were incorrect.
Hmmm... this tells us that experiments can be "fixed" to get desired results.  This is something to keep in mind!
One of my husband's professors in Bible college said that people are more likely to believe the view of someone that they like, often not even checking things out for themselves.  But they also might not even consider something another person says.
This is prejudging!
This is like what we read about in Module 1.  Scientists were either believed or not believed based on past achievements, not current facts.  There is some merit, of course, when a scientist is known for his accomplishments.  And if we hear of something we've never heard before, we should be open-minded but be examining the evidence ourselves.
Proverbs 18:13
"He that answereth a matter before he heareth it, it is folly and shame unto him."

We look at Module 1 and wonder how can people have believed such things, and not even listened to other scientists who had counter-examples to disprove previous theories.  Writings were banned from being read; scientists put into prison, and wrong things were being taught for years without even considering something different!
Well.... the same thing is being done today!
Evolution is being taught as a fact, and Christianity is not even considered.
►Read this article New Definition of Science?

Further in your module, you will read that sometimes correct results do not happen as quickly as they did in Experiments 2.1 and 2.2.  One such hypothesis was worked on for several years then became a theory that was tested repeatedly and believed for 25 years!  This was finally disproved with a counter-example in 1986, which isn't that long ago.  It may seem long ago to you, but actually it was probably around 10 years or so before you were born.

I couldn't find any scientific videos about counter-examples, but I did find an episode of Cyberchase that deals with a counter example, haha!
If your parent allows, you can watch Part 1, Part 2, and Part 3.


(2) p. 40-44, The Scientific Method
What is a Hypothesis?

The Scientific Method

►Scientific Method flow chart

Part 1

Part 2

Exp. 2.3, The Broken Flashlight.
In this experiment, you were to only change one thing at a time.  This is important!

My daughter's computer monitor had been staying pink!
We didn't know if it was the actual computer hard drive, or if it was the monitor.
Our hypothesis was that it was the monitor.  So our experiment to test our hypothesis was that we switched it with an old monitor that we had, and then she did not have a pink screen anymore. 
Yay!  We verified our hypothesis.  
But... then something happened. A counter-example.
My daughter didn't like that huge monitor because it took up so much space on her desk, so we switched again, and gave her mine (it had been having problems too), and I used hers.  (total 3 monitors, not to get you confused or anything!)  =)
This time we only switched our monitors, and not cords, (because the old monitor needed its exact cord).  I had her monitor with my cord, and the screen was not pink.  She got my monitor with her cord, and she had a pink screen.
So our first hypothesis was wrong.  It was not the monitors.  
We had changed 2 things without actually realizing it.  We changed the monitors and the cords.  
The pink screen was gone the first time around, so we had solved the problem, but we did not have the correct explanation.
To correctly do science, you must explain, not just fix.
We did some more experimenting just to be sure, and we finally determined that it was the cord. 
And that is our theory.  =)

In my last post, I told a bit about Ignaz Semmelweis, the Hungarian doctor who proposed that doctors wash their hands before going into the maternity ward.

Semmelweis, Pasteur, and Lister


(3) p. 45-48, Failures of the Scientific Method
In the late 1800's, Italian scientist Giovanni Schiaparelli observed several faint lines crisscrossing on Mars.  He published these observations, then American scientist Percival Lowell hypothesized that the lines were canals dug by the inhabitants of Mars, and eventually it became a theory.  Other scientists agreed and Lowell's theory was on its way to becoming a scientific law!
Of course, as more powerful telescopes were made, all this was discovered to be untrue.
However in 1952, there was a film made called Red Planet Mars.  Here is an excerpt.

Lowell did the right thing in following the scientific method, but sometimes we don't get the results expected.  Sometimes after a LOT of hard work, hypotheses and theories can be disproved!  The scientific method is the proper way to go, but remember, if you are doing true experiments, you don't know what the results will eventually be!
Even modern scientists make mistakes.  That is why things must continually be tested and corrected if need be.

In 1911, Dutch scientist Heike Onnes discovered the phenomenon of superconductivity.  He found that certain substances at extremely cold temperatures (about -450°F) did not resist the flow of electricity at all.
It's like no friction to slow things down.
At the time no one could explain how superconductivity worked.
Scientists have since discovered other ways to use superconductivity, not only through wires, but with magnets.  It's the super cold temperatures that allow this.
Here are some modern examples so you'll have an idea of frictionless superconductivity.
(A bit loud at the beginning.)

Bardeen, Cooper, and Schieffer - the BCS theory
In the 1950's, these scientists began to work on a hypothesis to explain superconductivity.  By 1960, it was considered a scientific theory.  Many tests were performed and confirmed for the next 25 years, and the BCS theory became accepted as a scientific law.

However, one aspect of the BCS theory was that superconductivity was impossible at any warmer temperature than -405ºF.
But in 1986, two scientists, J. George Bednorz and Karl Alex Muller found an example of superconductivity at a warmer temperature!
Turn your speakers up. This isn't very loud.

Since then, warmer and warmer temperatures have been found that allow superconductivity.  I say warmer, but they are still extremely cold!  =)
More examples of what is being done with superconductivity.

All this is to show that while something may have become a scientific law, a counter-example may show otherwise!  So scientists should ever be experimenting, always trying to better their results, discover more, etc.


(4) p. 49-50a, The Limitations of Science
According to p. 49, science
(a) cannot prove anything
(b) is not 100% reliable, and
(c) must conform to the scientific method.
You may be surprised to hear that science cannot prove anything!

I also found this statement in Science Magazine.  (bottom of 2nd page, middle column)
"...science doesn’t “prove” theories.  Scientific  measurements can only disprove theories or be consistent with them. Any theory that is consistent with measurements could be disproved by a future measurement."


(5) p. 50-55, Science and Christianity
I was pretty sure I would find no videos to go along with this section of your science book.  =)
This section looks at the Bible to see if there is any evidence that supports or contradicts that the Bible is true.  It gives several prophecies that have been fulfilled.   One prophecy mentioned in your text came from Ezekiel 26 and another from Zechariah 11:12-13.
One thing I got from reading this section was that just because many people say it doesn't automatically mean it is true.  Evolution is widely believed, but as a Christian, I believe God created the earth, and that He didn't need evolution to help Him do it.
But just because Christianity is also widely believed doesn't automatically mean it is true, either.
How do we know what is true?  Do we use science to prove it?  We already learned that science cannot prove anything.  There is a lot of evidence of an Intelligent Creator.  If we believe that some wristwatch parts cannot fall together and make a watch, how then could we believe that something so complicated as the human body, animals, the ecosystem, or the solar system could just fall into place with no designer?
Evolution claims we evolved over millions of years.  Why then, did it stop?  We aren't perfect yet, after all!
God created the world only once.  He doesn't need to create another one.  He gave it to us and told us to replenish the earth and subdue it.  It is up to us how we live in it.
So what about science?
I love the reply given with the answer to the On Your Own question 1.10.  Jay Wile writes,
"You should never use science as the basis for your world-view because the conclusions of science are always tentative.  Your worldview affects everything in your life.  You should never base something that important on something as tentative as science!"
If a person is not a Christian, he has no idea what it is like to pray to the Lord and have prayers answered; to feel peace in your heart after a loved one's death, knowing you will see them again in heaven.

I John 5:11-13
11.  And this is the record, that God hath given to us eternal life, and this life is in his Son.
12.  He that hath the Son hath life; and he that hath not the Son of God hath not life.
13.  These things have I written unto you that believe on the name of the Son of God; that ye may know that ye have eternal life, and that ye may believe on the name of the Son of God.
As Christians, we have the Holy Spirit that the Lord gave us.  If we are in a close relationship with the Lord, we will "hear" when the Holy Spirit guides us in everyday decisions.  It isn't magic.  To be in a close relationship with someone, you talk and listen to them daily, and often.  It's the same with God.  If we don't read our Bible and pray and listen to Him, we will feel far from Him.
An unsaved person doesn't have the ability to know or feel the things we do.  He feels that what Christians believe is foolish.  He actually isn't able to understand what we know.  Christians have the Holy Spirit of God to help us understand (discern) the Bible, and even without "proof," we know it is true.

I Corinthians 2:14
"But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him:  neither can he know them, because they are spiritually discerned."