Some top science experiments for children include making crystal geodes, creating dyed flowers and creating a transparent egg. Some other top experiments are making dry ice bubbles, making a rain cloud inside a bottle and making a miniature volcano.
To make crystal geodes, coat the inside of a plastic or real eggshell cut in half with glue, such as Elmer's glue, and sprinkle it with alum powder that contains potassium. Allow the glue to dry over 24 hours. Next, make the growing solution by boiling 2 cups of water mix with the food coloring dye of your choice. Stir 3/4 cup of alum powder into the water, and stir until the powder completely dissolves even if you have to reheat the liquid. Place the prepared eggshell in the liquid for 24 hours. The crystals grow larger the longer the shells stay in the solution.
To make a transparent, bouncy egg, place a raw or hard-boiled egg in a jar filled with vinegar. Cover it, and place it in a dark place for at least 48 hours, changing the vinegar after the first day. The shell dissolves away and the egg is bouncy because the vinegar thickens the membrane while turning it transparent.