Planting sock seeds can be an exciting way to find out what natural plant life you have growing around your town. Slip a pair of old socks over your shoes, then go on a short hike around your house or school. Take off the socks, then cut down the middle of each one to create two flat cloths. Line a shoe box with plastic wrap, then fill it with potting soil. Place your flattened socks onto the potting soil, covering it with a 1/2 inch layer of soil. Water the soil, then place the box in a sunny location. After a few weeks, you will see what seeds were collected on your socks when the plants have grown out of the box.
Homemade periscopes are not only educational, but can be played with for hours. Start by cutting the tops off of two empty and clean 1/2-gallon milk cartons, around three to four inches below the opened top. Discard the tops. Place the opened milk carton bottoms on top of each other, and tape them together with duct tape. This will create one large rectangle. Cut out windows from the box, cutting one at the top of the box and the other at the bottom of the box on the opposite side. Slide a mirror into the bottom window, angled diagonally facing upward, and tape it into place. Slide a second mirror into the top window, angled diagonally facing downward, and tape it into place. When you look through one of the windows, you will see through the other window.
String telephones are one of the oldest and most effective ways to teach that sound waves can be carried along a line and amplified, similar to a modern telephone. Simply drill a hole through the bottom of two tin cans, and insert the ends of a very long piece of twine into each bottom. Knot the ends on the inside of the cans so that they stay in place. Make sure that the twine is long enough so that one person can stand quite a distance from the second person when using the string telephone. When you speak into one of the cans, the other person will be able to hear it clearly when holding her can to her ear.