Favorite Website: The Science House

The Science House is a program by NC State University, to help K-12 teachers with hands-on math and science learning. 

You could spend a lot of time exploring the whole site (and I recommend that you do), but I'll point you in the direction of a few of my favorites...

I'd head to the investigate page first, as it'll take you to lists of inquiry activities you can do with your students. 

I've spent the most time in the Countertop Chemistry section, in fact, that's how I first came across The Science House.  I have found this Commercial Equivalent of Chemicals to be handy. 

Spend some time exploring and see what you can bring to your classroom!

Chemical Changes: Pennies, Salt & Vinegar

Dissolve some salt in a small amount of vinegar.

Hold one penny half way in the solution.  When you pull it out, you'll see this...

The part that was submerged in the solution is shiny copper.  The portion that remained out of the solution remains dull with copper oxide tarnish (dark brown and/or green).

Now put 20 pennies in the solution and let them sit for about 5 minutes.

Remove the pennies and...
Rinse 10 of the pennies off and let them dry.
Just let the other 10 pennies dry.

Rinsed pennies are on the left.

Now wait an hour or so....

(Rinsed pennies are now on top)

So, What Happened?

The vinegar/salt solution removed the copper oxide from the pennies, leaving a clean copper surface on each penny.

Over time, all of the pennies will become tarnished with copper oxide once again, as the copper reacts with oxygen in the air.

The vinegar/salt solution that remains on the pennies that were not rinsed speeds up the oxidation process, so in an hour you're left with pennies that look like this:

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Presented at the 2003 New Jersey Science Convention.

Cell Building Blocks: Testing Food for Fat

Gather a variety of food items (fruits, veggies, crackers, chips, cheese, bread, lunchmeat, condiments, etc.).

Spread open a brown paper bag on your work surface. Rub a small amount of each food item on the bag and label the spot with the type of food. After you have completed all of the food items, look for transparent spots – this is evidence of fat. Beware of spots that are just wet – they will dry out, transparent spots due to fat will not. You may want to rub a small amount of oil (a known fat) onto brown paper bag as a source for comparison.


Have students record data and look for patterns in the items that contain fat and those that don’t (think plants vs. animals).

Natural Resources: The Geologists' Dilemma

You'll need four different types of driend beans for this activity.  I used:
 - black beans for coal (not pictured abbove)
 - kidney beans for oil
 - navy beans/black eyed peas for natural gas
 - lentils/peas for nuclear energy

You'll need about 100 pieces of coal, 74 units of oil, 20 units of natural gas and 6 units of nuclear energy.

Hide the beans throughout the classroom.  I tell students they won't need to open drawers or doors to find the beans, but they may have to look behind objects that are sitting out. 

Divide your class into four teams of geologists - each team will search for their own type of energy.

After showing the students what each type of energy looks like, send them into the field for one minute to find their respective energy. 

After the minute is over, have them come together as a team and count the energy they collected and record the data on the board. 

Then send them out for a second round of searching.  Count and record.  Then have a third round.  Count and record. 

Then discuss...
...which energy was easier to collect?  Why?
...which energy was difficult to collect?  Why?
...what can you deduce about the cost of each form of energy?
...what parallels can you draw between this activity and the harvesting of natural resources in real life? 

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This activity came from the Women in Mining website, however it appears that it is no longer featured on their list of activities.  But, while searching for non-existent link, I came across this activity, of the same name.  If you're not afraid of a little mess in your classroom, I think this would be fantastic to try.  I love the solar energy analogy - there's an abundant amount of it, but it's tricky (and rather expensive) to harvest.

Measurement: Cubic Cm to mL

I don't remember how it came up, but one year I was talking with my students about cubic centimeters and how one cubic centimeter is the same as one milliliter.  It's not a concept my students use a lot, but a good one for them to start grasping.  Here's an activity to help them understand: 

Have students determine the volume of a centimeter cube* by measuring its length, width, and height and multiplying.  If done accurately, each of the dimensions should measure 1 cm, which gives a volume of 1 cm3.

Then have them determine the volume by water displacement.  If done accurately, it should have a volume of 1 mL.

There you have it - the same object has a volume of 1 cm3 and 1 mL - they are equivalent units.


*Ask the math and elementary teachers you know - they may have some centimeter cubes you can borrow (or even have) - you only need a few. 

You can then take it a step further... break out some other small blocks (this is a little hard... they have to be small enough to fit in a graduated cylinder).  Have students measure those in cm to determine volume.  Then have them determine volume by water displacement.

How Does That Work?: The Drinking Bird

Have you ever seen these little toys around?  You dip their beak in a cup of water, then the bird swings up and when he gets thirsty again, he'll dunk down and get some more to drink.  He'll do this over and over again. 

Can your students figure out why? 

The short answer has to do with evaporative cooling and vapor pressure.  For a longer answer, check here.

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How Does That Work is a series of products and demonstrations that you can present to your students and challenge them to explain the science of how they work. Make sure you decide ahead of time what you'll accept as a valid explanation - can it be printed straight off the internet, written in the student's own words, or does the student need to be able to explain it to you conversationally? What will a valid explanation earn the student - a prize, extra credit, a feeling of goodness?  

Friction: Give Yourself a Hand

No surface is perfection smooth – they all have bumps of ridges to a various extent.

Friction occurs when two surfaces rub against each other and those bumps and ridges catch on each other.

A notable by-product of friction is heat.

Have your students rub their hands together quickly. It doesn’t take much hand rubbing to notice a warm feeling.

Now put a small squirt of lotion (stick to unscented stuff for this) in each students hand.

Have them rub their hands together again – much less heat is generated.

The lotion acts a lubricant – it helps fill in some of the bumps and ridges on the surface of the hands, resulting in less friction and therefore less heat.

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Presented at the 2003 New Jersey Science Convention.