Photosynthesis

• Provide each student with a germinated pea seed. Instruct the children to plant the seeds and water them. Place half of the seeds by the window in the sunlight. Place the other half in a darkened closet. Continue to water and monitor the plants for the next 10 days, and then place the plants side by side. Encourage the children to discuss the differences. What happens if the pot that was in the closet is kept in the sunlight for several days? Explain how plants use energy from the sun to produce food through the process of photosynthesis.
  
  

Chromatography

• Divide the class up into groups and provide each group with different-colored candies, such as M&Ms or Skittles. Set each candy in a drop of water, and then dot the colored water along the bottom of a square piece of coffee filter. When dry, stand the filter in a 1 percent saltwater solution with the dried color spots just above the water line. The dyes from the different-colored candies will separate as the salt water moves up the filter. Explain chromatography and encourage the students to compare the results. Can they determine which dyes listed on the package were used for which candies?
  
  

Air Pressure

• Pair students into groups and provide each with a peeled, hard-boiled egg. Each group must also have a glass bottle, such as a fruit drink bottle, in which the mouth is slightly smaller than the egg. Light a strip of newspaper and place the burning paper into the bottle. Have the students cover the bottle opening with the egg. After the fire goes out, the air inside the bottle will cool. As it cools, the pressure drops, causing the egg to be sucked into the bottle. Explain how air pressure changes work both within this experiment and in the real world.
  
  

Recycling

• Ask students to tear a page of used paper into small pieces. Let it soak for 10 minutes. In a separate container, have them mix a fourth cup of water and an eighth cup of cornstarch to make a paste. Drain the excess water from the paper and mix it and the paste in a blender. Pour the mixture over a thin wire screen. Use waxed paper and a rolling pin to remove excess water and let dry. Once dry, peel it from the screen and write on the new paper. Discuss with students the importance of recycling for the global ecology.