Children want to know such things as where the colors in the rainbow come from and whether plants sleep. Their curiosity about the science behind everyday sights lends itself to interesting and educational projects for science. All scientists begin their research with an observation about the world. Third grade science projects can follow this same scientific method, which scientists and researchers use to make their discoveries.

This 3rd grade science project discovers how a growing chick breathes inside its hard eggshell. If the student examines an egg with a magnifying glass, he may see tiny holes called pores, similar to the pores in his own skin. He can use water to test whether air and other substances can get through the pores so that the chick can breathe.

To test this, fill a large bowl with water and add small amounts of liquid dish soap and bright food color. Soak several raw chicken eggs in the bowl for 24 hours. After that, crack the eggs open, and discard the insides. The student should make observations about what the inside surfaces of the shells look like. If the eggshell has any dye on the inside, that means the water was able to permeate the shell. The reason dish soap is added to the water in the bowl is to dissolve the inner membranes in the egg. If dye enters the egg, it might create visible patterns based on the locations of the pores. The membranes blur those patterns.

Most children can recall a time when they felt a zap after touching a surface. Caused by static electricity -- the buildup of an electrical charge -- the zap is the sudden discharge of that electricity. Friction creates static electricity by transferring electrons between two surfaces that have close contact. For example, if a student rubs a balloon over her head, a charge builds between the balloon and her hair, which results in a positive charge in one and a negative charge in the other. When she pulls the balloon slowly away, the opposite charges in her hair and the balloon attract each other, causing her hair to stand up. (See Resources).

In the same way, if the student rubs a balloon against a wool sweater and then presses the balloon against the wall, it typically sticks to the wall. She can devise an experiment to test how many times she needs to rub the balloon against a wool sweater to make it stick to the wall, and how long she can get the balloon to stick before it falls off.

To test it, rub the balloon against a wool sweater once and try to stick it to the wall. Then have the student time how long it takes to fall off. Touch the balloon to a metal object to discharge any static electricity before trying again. Rub the balloon against the sweater an increasing number of times with each trial, touching it to the metal object after each turn. Continue until the balloon has stuck to the wall at least five times. The student can now draw conclusions about the balloon and static electricity. Consider whether different weather conditions or materials might affect the outcome.

Silly Putty is a stretchy, bouncy brand-name toy made of substances called polymers. In this project, the student will experiment with making a homemade version by altering the ratios of the ingredients. White glue is made up of a polymer called polyvinyl acetate, and the cleaning product Borax detergent powder made up of a chemical called sodium tetraborate. These two chemicals react together to form the stretchy material the brand-name toy. In this project, the student mixes varying ratios of the chemicals to observe differences in the resulting material.

Mix equal amounts of white glue and water in a glass jar. The student can add food dye for a colorful result. Cover the jar with a lid and shake it until the clumps disappear. Add 2 teaspoons of Borax to 1 cup of warm water in a second jar. Cover and shake it until the mixture is clear. Label four zipper storage bags from 1 to 4 tablespoons. Add a corresponding amount of the white glue mixture to each bag.

Add 4 tablespoons of the Borax mixture to the first bag. Add 3 tablespoons to the second bag, 2 tablespoons to the third bag, and 1 tablespoon to the fourth bag. The student should close each bag and squish the materials to mix them. When the mixture begins to look like a sticky lump, he can remove it from the bag and play with it. Record how it acts when he stretches, squeezes or bounces it. Observe whether it is more solid or liquid, and whether it feels sticky or slimy to the touch. He can choose which ratio makes the best toy, and name his product. Throw away any leftover ingredients in the garbage because they can clog drains.

An important part of science projects for school is the display board. At the end of the project, a trifold board offers an eye-catching and digestible way to present science project results. Come up with a creative title that draws people in for a closer look. Arrange the items on the board so that they lead down and to the right, in columns like a newspaper.

Have the student place her hypothesis in a prominent area. Display the results; Charts and graphs can help people absorb the information at a glance. Have her place her conclusion on the bottom right of the display board. Three-dimensional art, bright colors and photographs all make the presentation more interesting for both the student and her audience.