An idea for a biology project that your elementary students will be enjoy completing involves seeing whether whole and sliced lemons will float. First, separate students into small groups and get them to fill a bowl with water, two-thirds-full. Students should drop a whole lemon into the water then draw a picture of the outcome -- the lemon will float on the surface of the water. Now, take the lemons and slice them up on a chopping board before giving them back to students to drop in the water. Have them draw the result -- the single slices of lemon will sink. Get students thinking about the composition of a lemon and why the whole lemon floats while slices sink.
One example of a fun and easy elementary chemistry project involves taking dirty old pennies and making them bright and shiny using vinegar or cola. Supply students with a handful of grubby cent coins and two beakers -- one with regular tap water and the other with vinegar. Have students leave the two beakers in the same environment overnight and teach them about controlling variables, as the two beakers are exposed to the same atmospheric conditions. The next morning, students should strain the two beakers and compare the condition of the coins -- those left in vinegar will be bright and shiny, while those left in water will be largely unaffected.
A good way to get your elementary students thinking about the forces of physics is the egg in a bottle experiment. Sit your class around a table before demonstrating this fun and quick project. Take a cleansed, empty bottle, such as a used soda bottle, and place a hard-boiled egg with its shell removed into the neck of the bottle -- students will observe as the egg sits in the bottle neck. Now, remove the egg, strike a match and drop it into the bottle (make sure it stays lit) and place the egg back into the bottle neck -- students will witness the egg sucked into the bottle as the oxygen is consumed by the burning match in the bottle.
Invite your elementary level students to think about global issues when completing an earth science project. One fun, easy project gets them to consider the greenhouse effect within the classroom. Get students to lay out two thermometers on tea towels next to one another. Place a thick glass dish over one of the thermometers. Then, get students to set up identical desk lamps so they are situated in the exact same position over each thermometer with the same wattage of bulb. Take a base temperature reading from each thermometer before turning the two lights on. Get students to note the temperature every 2 minutes before concluding the experiment after an hour. Get students to think about why the greenhouse condition thermometer is much warmer than the thermometer without the glass dish.