Science Fair Ideas for Girls

A science fair is a great way for a girl to learn new information about science topics or get answers to her questions. Fun science fair projects can be in such areas as life science (plants, animals and the environment), earth science (weather, geology or space) and physical science (chemistry, physics and matter).

Mentos and Diet Coke

For this experiment, the student will need 12 mint-flavored Mentos candies, a two-liter bottle of Diet Coke, a two-liter bottle of tonic water, dental floss, an upholstery needle, safety goggles, a measuring tape and a disposable poncho. The young scientist will need to carefully string six Mentos onto a piece of dental floss, and tie a knot on one end of the floss so the candies don't fall off. After this is done, she'll need to put on the poncho and safety glasses before placing the string of candy into a full, open two-liter bottle of tonic water in an open area outdoors. The candies will create a reaction within the bottle that will cause liquid to bubble out. The student will then use the measuring tape to estimate how high the bubbles burst out of the bottle. To continue with the project, more candies need to be strung onto a piece of floss and dropped into a full, open two-liter bottle of Diet Coke. The student will then measure how far the soda shot up into the air with the measuring tape. For the fair's presentation, she should explain her experiment, stating why the Mentos caused the Diet Coke to erupt out of the bottle farther than the tonic water. Older students can outline how the reaction can be explained chemically using the equation [CO2 (l) ' CO2 (g)].

Shiny Pennies

This experiment measures the effects of gentle chemicals on copper. The student needs to collect the following: 20 dull, dirty pennies; cup white vinegar; 1 teaspoon salt; a shallow glass bowl and paper towels. The salt and vinegar should be mixed until the salt is dissolved. The student then places all the pennies in the bowl of vinegar for five minutes. Half of the pennies should be removed and placed on a paper towel. She should completely rinse the other pennies with water, and place them on a paper towel that has "Rinsed" written on it. After about an hour, she will notice the pennies that weren't rinsed have turned green. For the fair, the student should describe how copper oxide dissolves in a mixture of acid, but can then turn greenish color when exposed to oxygen.

Crystal Growing

The student will grow different types of crystals at home for this easy project. Materials needed are black construction paper, scissors, three shallow bowls, warm water and 1 tablespoon each of three types of salt (table salt, kosher salt and Epsom salt are recommended). The student should dissolve each type of salt in its own 1/4 cup of water, and then pour the water into a bowl lined with black construction paper. The bowls of water should then be placed outside. When the water evaporates each salt will have formed different crystals on the pieces of black paper. The science fair presentation should explain that each type of salt has different chemicals, thus creating different types of crystals.