Sep 8, 2014

Mad Scientists Take Two (Balloons & Electricity)

This book totally became my go to for science projects at the library. 
All of the experiments I used in this program came from this book!
Balloons, Plastic Cups, Hex Nuts (of various sizes), 1 Fluorescent Light Bulb, Lemon Juice, Paper Towel, Nickels & Pennies, and bowls for the water. 

The Experiments:

1. Balloons and Air Pressure Challenge. Found on page 134. Each table has a bowl of water, a few balloons and a bunch of cups. I used one balloon per kid and about 15 cups per table (the successful tables needed more cups). I first asked the kids how many cups they thought we could get to stick to a balloon, and I showed them how I could stick one cup to the balloon. Process: After one child blows up the balloon to about grapefruit size, another child dips the top of 2 plastic cups in water and then uses the surface tension to hold the cups to the balloon. The first child blows more air into the balloon, the air pressure inside the cups changes so the cups stick to the balloon. Pause for more cups, and keep blowing and sticking cups on as long as you can. The challenge was to get over 10 cups on a balloon and one group of kids did it!

2. Balloon Banshee. Found on page 182. Each child has a balloon and a hex nut. I challenged the kids to make noise with their balloons using both of the items. Eventually one of the kids figured it out: put the hex nut inside the balloon and use two hands to get it spinning along the inside of the balloon. As the sides of the nut hit the inside of the balloon, they make a vibration. The faster you can get the nut going around inside the balloon, the more constant the sound is until it sounds like a very annoying banshee. I went around and blew up balloons for kids who couldn't and stuck a nut in and tied it off. Each child got to take one of these fun noise makers home with them!

3. Light a Lightbulb using a Balloon. Found on page 200. Can it be done? First we tried rubbing the balloon on a kids head. Rub and have the kids sing a fun song like the ABC's (it's corny, but they'll do it). Turn off the lights (have a helper do that), stick the balloon to the end of the bulb. We didn't get it to work, we tried it again and sang the ABC's backwards, still didn't work. I had some wool yarn, we tried that and I had the kids count by 5's to 100 as we rubbed. We were able to get a short spark out of the light bulb! The kids came up with different scenarios that we tried out to get the light bulb to light up with the balloon.

That was the transition for building a battery out of money (electricity)

Can we make electricity with money?

4 (& 5). Penny & Nickel Battery. Found on page 192 (I had to wait for the book to come back to the library to find out the correct number of coins for this post). Each table had a small cup of lemon juice, paper towel squares cut into 1" squares, a few sheets of paper towel to lessen saturation levels, and 6 of each clean pennies and nickels (cleaned the night before).

Waaaay back at the beginning we had put the money into different bowls of water: one with soap, one with salt, one with lemon juice and one with vinegar and made predictions about which would be the cleanest (it didn't work how it was supposed to, but that was okay it's more about making predictions and testing them out). The kids all looked at the money to determine the results. As they came up to look, one rep from each table took back 6 of each: pennies and nickels. Then they worked on creating their batteries.

When the paper towel is dipped in the lemon juice and placed between the pattern penny, nickel, penny, a slight charge will be created when you hold each end of the "wet-cell battery". Some of the tables got it to work, and some didn't. We predicted it was because of the amount of moisture on the paper towel squares, but ran out of time to test our hypothesis!