Instruct your fifth-graders to carry out a project that compares planting runner bean seeds in soil or hydroponic conditions. Have students take four identical plastic cups and fill two of them 2/3 full with potting soil before planting a pair of runner bean seedlings in each one, roughly 1/2 an inch beneath the soil's surface. Students should prepare their hydroponic plants by first saturating four runner bean seedlings with water in a peat pellet before filling the remaining two cups with distilled water and placing hydroponic potting nets so they are touching the water in each cup. Hydroponic potting nets are a small plastic cradle that hold the roots of a seedling in water, while allowing the plant to grow in the open air. Have students place the peat pellets and seeds inside the net. Instruct students to water once every three days, watering the soil in two cups and sprinkling water over the hydroponic cups. Students should observe the plant growth for at least three weeks before deciding which growing conditions are best.
Conduct this simple classroom experiment to demonstrate to your fifth-graders the interesting characteristics of cornstarch as a colloid. A colloid is a substance with microscopic drops that disperse evenly through another substance, such as ketchup. First, have students lay out a few sheets of newspaper as things can get messy. Then students must mix one measuring cup of cornstarch with two drops of food coloring. Get youngsters to then slowly pour 1/2 a cup of water into the bowl and mix with their fingers until all of the powder is damp and slightly liquid --- Exploratorium.com recommends tapping the top of the cornstarch with the back of a spoon and, if it splashes, adding more cornstarch, or if is still powdery, add more water. Have students then pick up a handful of the mixture and squeeze it --- they will note it becomes solid. Students should then release their fingers and note that it returns to liquid form and falls through their fingers into the bowl.
Conduct this experiment to get your fifth-grade students thinking about the varying strengths of geometric shapes. Students should first decide on three shapes they wish to test, such as a cube, rectangular prism and a pyramid, before hypothesizing as to which they think is the strongest and weakest. Have students construct geometric shapes using one-inch diameter plasticine balls and bamboo sticks. Students should then add weight to the top of their geometric shape by placing one small sandbag or beanbag on the center of the top of the shape. Instruct students to count the number of bean or sandbags required for the shapes to collapse before concluding which geometric shape is the strongest and weakest.
One interesting earth science project that fifth-graders can complete gets them to generate the conditions necessary for the formation of frost. Students should first fill a regular glass 3/4 full with ice cubes before covering the ice with water and wiping dry the exterior of the glass with a paper towel. Have students pour four tablespoons of rock salt over the top of the ice and gently shake up the ice a handful of times. Students should start a timer and, every 15 seconds for three minutes, scratch their fingernail on the outside of the glass until they observe the formation of a thin film of ice.