Monday, October 31, 2011

Candy Cell Models

One week of candy wasn't quite enough, so here's one more!  Happy Halloween!

A good friend did this with her 5th grade students following Halloween one year, and it was a great success. 

The students were studying cells and they were placed in groups and instructed to make a cell model using different types of candy.  The students rationalized what would work best for each organelle and each contributed some candy from their own stash to create the finished product. 

The students enjoyed their work and their parents were quite happy to have the candy put to use other than eating!

And, this activity could be adapted to whatever you happe to be studying right around Halloween.  Students could use candy to make models of body parts/systems, atoms, viruses, bacteria, etc.

Sunday, October 30, 2011

Jello Brain Update!

Remember the free Jell-o brain molds I told you about? 

Well, they arrived a couple of weeks ago. 
For size comparison - that's a 5 year old head it's next too (albeit a rather large 5 year old head....)

I haven't put mine to use yet (have to remember to get more Jell-o at the grocery store...), but my friend Susan got hers and tried it...

Photo from Susan at Learning ALL the Time

Fun stuff! 

If you're interested, you have through Monday (October 31) to get a free mold (only pay $2.95 shipping and handling).  After Halloween, it's regularly priced - $2 + Shipping. 

If you'd like one, head to the Kraft Corner Store!  You'll have a head start on next Hallween, and some interactive Central Nervous System lessons in the meantime!

Friday, October 28, 2011

Website: Candy Experiments

I've shared a number of candy-based learning opportunities this week, but I wanted to draw your attention to a website dedicated to this topic alone. 
You can find additional experiments at Candy Experiments, as well as some you've seen here (what can I say, great minds think alike!). 

In addition to several new experiment ideas, Loralee also has made instructional printables available would be great for setting up lab stations or party stations (and I LOVE the idea of handing them out along with the Halloween candy) and tips for running a successful candy experiment party.

Have fun exploring, and then playing!

Thursday, October 27, 2011

Denisty: Candy Density

This is really just another way to get your students to practice measuring and calculating density.  But, it involves the use of candy, so it's more interesting than your run-of-the-mill density calculation.

The original version of this activity uses Whoppers, Lemon Heads and jelly beans.  You could certainly modify that to use whatever you have available and/or is on sale.  However, you will want to make sure you have a variety of densities present in your candy selection.  The Whoppers are nice, because they will float.

You'll want students to use 3 pieces of each candy, so they can average their data.  (This could be done in groups, to save time and candy usage).

First have students find the mass of each piece of candy.  Then they'll find the volume via water displacement.  Because the Whopper floats, they'll need to use the tip of a pencil to push it down, so it's just below the water surface.  Finally, they can calculate the density.

If you wish to take it a step further....
After calculating the density of individual pieces of candy, have them calculate the density of all three pieces at the same time.  The mass and the volume will each be lager than they were for the individual pieces, but the density will remain the same (assuming all measurements and calculations are made accurately).  It's a good opportunity to remind students that density is an intensive property, not dependent upon the amount present.  And, by making it a hands-on reminder, your students are more likely to remember it!

Wednesday, October 26, 2011

Density: Sink or Float: Candy Edition

Same idea as the original Sink or Float activity, but it uses candy instead.  Again, it's good for the preschool and early elementary set.  (I've got a candy density activity for older students coming tomorrow). 

Gather an assortment of candies.

Hypothesize which candies will sink and which will float.  Divide the candy into appropriate piles. 

Then test!  You may want to test the candy first with the wrapper on and then with it off - why do some candies float when they're in the wrapper, but sink when they're unwrapped? 

After seeing which candies float and which sink, you may want to slice or break some of them open to look at the inside.  See if there are any clues to help you figure out what some float!

Tuesday, October 25, 2011

How Much Does Taste Depend Upon Smell?

Ever noticed that food doesn't seem to have as much flavor when you have a stuffed-up nose? 

A large part of your taste sensations come from smell, so when you can't smell very well, your sense of taste declines as well.  I've used Dum-Dum lollipops for this experiment, since they come in a multitude of flavors and we always seem to have a large number of them around the house after Halloween!

Have students work in pairs to do this experiment.

One student, the taster, closes her eyes and uses one hand to plug her nose.  The other student, the assistant, will then unwrap a randomly chosen lollipop.  He then hands it to the taster, who puts it in her mouth, while keeping her eyes closed and nose plugged.  The taster tries to identify the flavor of the lollipop.  The assistant records the taster's hypothesis. 

After making an initial hypothesis, the taster is then allowed to unplug her nose.  She tries again to identify the flavor of the lollipop.  Again, the hypothesis is recorded by the assistant.

And finally, the taster can open her eyes to view the lollipop, and make any final changes to her flavor guess. 

At that point, the flavor of the lollipop can be revealed and the two students can switch positions.

Of course, you don't have to use lollipops - any candy that comes in multiple flavors will work.  An experiment was put together as a follow-up to a Newton's Apple episode, in which jelly beans are used.  Check out the experiment, the explanation, and make sure you read the "Try This" suggestions at the end - I think I want to try the potato and apple experiment!

Monday, October 24, 2011

Candy Week!

For better or for worse, Halloween is synonymous with candy.

From past experience, I can say that your students' parents will be more than happy to have their kids sacrifice some of their trick-or-treating loot in the name of science and education!  And, November 1 is a good time to find candy on sale, if you're in need of more.

So, this week I'm going to share some experiments, activities, and demonstrations that use candy in one way or another to help your students learn and understand scientific principles. 

The mind reels that I could possibly have more candy-based learning to share; but, I do!  What can I say, there's nothing quite like candy to get and hold you students' attention! 

Before I bring on the new stuff, here's a round-up of science activities starring candy previously featured on the Science Matters blog:

How Many Licks Part I and Part II

Friday, October 21, 2011

Body Systems: Skeletal System: Skeleton Race

Assembling a skeleton relay races are regularly used as Halloween party games, but adding a few extra requirements can turn it into a great review lesson.

Ideally you'd use pieces from snap-together skeletons, but if you don't have those on hand, find an appropriate skeleton to print.  Searching "printable skeleton" will give you a plethora of options, many of which are in pieces that need to be assembled.  Pick one that has appropriate detail for your age group and prepare the pieces.

Divide the class into teams.  The smaller the teams, the more practice each student will get, but it will require more skeletons. 

Each team will need a bowl of skeleton pieces, placed on the front table/teacher's desk.  Each team will work at a separate table/desk.  At that desk they'll need a piece of paper on which to assemble their skeleton and a glue stick.

The first person for each team approaches their bowl of bones and chooses one.  The student studies the bone and has to correctly name the bone before he/she can take it back to the team for assembly.  Once the bone has been brought back to the table, another team member can go retrieve a bone. 

If a student cannot correctly identify the bone they have chosen, it is returned the bowl and the student returns to the team.  The team has to wait out a 15 second penalty before sending the next team member forward. 

Once all the bones have been collected, the students glue the skeleton together.  First team with a correctly assembled skeleton wins! 

Thursday, October 20, 2011

Body Systems: Skeletal System: Bone Model

I was inspired by the edible bone models I've come across, to create a non-edible bone model I could keep in the classroom for use year after year, and pull out at a moment's notice.  The supplies are readily available at hardware stores and craft stores.  I hope you find it useful. 

You'll need:
~10" foam pipe insulation
~10" 1 1/2" PVC pipe
Model Magic clay
red yarn
fabric pieces

Begin with the length of foam pipe insulation to use as the spongy bone.  Split the insulation open to reveal the hollow tube in the center, perfect for holding the bone marrow. 

Roll the clay into a snake that fits the center of the pipe insulation.  While you're rolling the clay, embed a length of red yarn in the clay to represent a blood vessel traveling through the marrow.

Slide the completed spongy bone and marrow into the length of PVC pipe.  This is the compact bone. 

Use the fabric to create a tube into which the PVC pipe can slide.  This is the membrane covering the bone. 

I added a few pieces of Velcro, to attach the blood vessels. 

And finally, wrap the outside of the fabric with additional lengths of red yarn - more blood vessels.  (I should add some blue yarn as well....)

I'm really quite pleased with my model.  It can be taken apart and put back together again and again and I think it will be quite useful in the classroom.

Because you usually have to buy 10' lengths of PVC that you have to cut yourself, some of you might be turned off by this project.  I've got extra materials from making my own, as well as easy access to additional supplies, and a willingness to make up some additional models.  If you're interested in purchasing a pre-made model (or several), send me an email and we can discuss the details.

Wednesday, October 19, 2011

Body Systems: Skeletal System: Edible Bone Model

Do you know what your bones are made up of?  They contain two types of bone tissue: compact bone and spongy bone, bone marrow, and a thin covering.  Blood vessels continuously carry blood to and from the bones. 

If you'd like to make it easier for your students to remember the components of bones as well as their properties, consider having them make an edible model of a bone. 
Pretend that the red yarn is Twizzlers Pull & Peel strings.  I forgot to get them at the grocery store, but had everything else and didn't want to hold things up, so I substituted.

To make your bone model, you'll need:
lady fingers
sugar wafers
strawberry jam
Twizzlers Pull & Peel

Place the tortilla on a plate. 

Open the lady fingers and place them along the center of the tortilla.

Spread the lady fingers with the jam.

Lay the licorice down the middle of the lady fingers. 

Sandwich the lady fingers together.  Place the sugar wafers along the sides of the lady fingers.

Wrap the whole thing in the tortilla.

Wrap another piece of licorice around the tortilla.

Your model is complete!  But, before you eat it, make sure you note what each part represents:

Licorice strings are blood vessels.
Strawberry jam is the bone marrow.
Lady fingers are the spongy bone.
Sugar wafers are the compact bone.
The tortilla is the membrane covering the bone.

One version of this activity can be found here, but I first learned about it elsewhere.  I have no idea what the original source is.

Tuesday, October 18, 2011

Body Systems: Skeletal System: Why You Need Calcium

For this demonstration, you'll need a clean chicken bone* (a drumstick works best) and a large jar filled with vinegar.  You'll also want some way to close the jar, either a lid or some plastic wrap.

Observe the bone, try to bend it (but don't actually do so, you want to keep it in one piece).

Place the bone in the vinegar and cover the jar.

Remove the bone from the vinegar every day for about a week.  Observe and test for flexibility.

Over the course of the week, the bone will become more and more flexible, taking on a rubber-like feel by the end.  The vinegar (acetic acid) breaks down the calcium deposits in the bone, allowing you the opportunity to observe the importance of calcium in maintaining bone strength.

**The next time you have chicken or turkey, you may want to clean the bones and stick them in a resealable bag in the freezer, so you have them when you need one.

Monday, October 17, 2011

Body Systems: Skeletal System: Pasta Skeleton

Skeletons are a common sight around Halloween, and as such, I thought I'd spend a week sharing skeleton/skeletal system/bone activities and lessons you can do with your students.  They're perfect for Halloween mini-lessons or any time your curriculum brings you to those topics. 

First up, pasta skeletons!

The great variety of shapes of pasta in which pasta comes make it a fun (and inexpensive) medium with which to create. 

Provide your students with an assortment of pasta shapes and black construction paper and let them create a skeleton, being sure to include the bones you've required them to learn. 

Another possibility, have them create a more detailed model of one part of the body.  While searching for something else, I found this document, which includes an activity in which students create a model of the bones in the hand using varying sizes of tube-shaped pasta.

Friday, October 14, 2011

Fun Products: Water-Absorbing Crystals

In preparation for some Halloween fun, you might want to consider getting your hands on some water-absorbing crystals.  They come in a variety of names and can be found in all sorts of locations.  In short, you're looking for a small crystal that can absorb large quantities of water. 

Sodium Polyacrylate is the polymer used in diapers to absorb large quantities of liquids.  You can get it from Educational Innovations, among other sources.  It's great for "disappearing" water magic tricks.  You have a small amount of the powder in a cup.  Pour in some water and a minute or so later, turn the cup upside down and nothing comes out.  (For your performance, you'll want to use an opaque cup, but I wanted to let you "in" on the action).

Ghost Crystals (also available from Educational Innovations) are lots of fun. This are much larger crystals than the sodium polyacrylate.  After you've enlarged your crystals, very carefully tie a thread around a single crystal.  Fill a water bottle with water and submerge the crystal, on its leash, in the water.  Leave the thread hanging over the side of the water bottle and screw on the cap.  Tell your students you've brought your ghost pet to visit for Halloween day.  They'll look and look, but all they'll see is a leash suspended in the middle of the water! 

It's also fun to trick your student with some "chunky" water.  A clear container filled with the enlarged crystals and a small amount of water will look just like a glass of water.  Fill a pitcher with the polymers and offer to pour a student a glass of water - instead of a stream of water, chunks will come out of the pitcher.

Other places to find water-absorbing polymer crystals:
Steve Spangler's Water Jelly Crystals look to be of a similar size to the ghost crystals, if you prefer to shop there. 

I've seen similar products (I'm not sure of their exact chemical make-up, but they function in the same way) at:
Toy stores (random locations within the store)
Garden centers (as an additive to retain moisture in soil)
Craft Stores (usually in the floral area)
Science supply catalogs

Lots of fun for Halloween or April Fool's Day, but also useful when studying polymer chemistry!

Thursday, October 13, 2011

Update: Momentum in a Collision

Last winter I shared my Momentum in a Collision activity with you, in which students used rulers to create ramps down which they rolled marbles of varying sizes to observe the transfer of momentum in action. 

Since then, I've had a brainstorm of another, more qualitative way, to complete the activity.

If you know of any young train fans, see if you can get your hands on their wood train tracks, especially the rise-and-fall tracks. 

The parallel grooves on the tracks allow you "run" two marbles at a time and compare the transfer of momentum as they crash into different sized marbles at the end of the hill. 

Train tracks also give you the opportunity to create a nice long runway for the marbles to roll along until they run out of energy. 

Wednesday, October 12, 2011

Microscopes: Elodea Lab

Altay Scientific Prepared Plant Microscopic Slides: Elodea submerged leaf; WM
Elodea is an aquatic plant that can be found at most fish stores. It is great for looking at under the microscope because the leaves are so thin, only a couple of cell layers thick and light can pass through the leaf.

Place an elodea leaf on a clean slide. Place a drop of water on the leaf and then the cover slip. View under the microscope. You will note the regular, retangular shape of the plant cells, the cell wall, the chloroplasts, and the nucleus.