Leaves in the Dark

Plants need their green leaves to convert sunlight into energy to grow and live. In this science fair project students observe what happens to those green leaves when they do not receive sunlight. Students know plants and people are different, this project gives them an opportunity to explore one of those differences.

Outlined in this project is the purpose and hypothesis to help clarify the point of the project. The approximate duration, a short materials list, and an easy to follow procedure is also included. Finally, questions to ask along the way and upon completion of the project are provided.

Purpose: Observe how leaves change when denied sunlight.

Question: What happens to a leaf when it can’t get any sunlight?

Hypothesis: If a leaf cannot get any sunlight then it will turn brown.

Statement: Green leaves will turn brown without sunlight.

Estimated Duration: 7 minutes a day for 7 days

Materials List:

  • access to a leafy plant
  • kitchen foil
  • crayons, paper and pencil
  • digital camera – optional

Procedure Outline:

  1. Find a plant with lots of green leaves.
  2. Draw or take a picture of the plant and one of its green leaves.
  3. Find a flat, dry shady spot (a sidewalk or driveway work best).
  4. Using 14 small pieces of foil, wrap 14 leaves so no sunlight can reach them. Be gentle, the leaves need to stay attached to the tree.
  5. Draw or take a picture of the plant and one of the foil wrapped leaves.
  6. After one day, remove the foil from two leaves and draw or take a picture of them.
  7. Remove the foil from two leaves each day, drawing or taking a picture each time.

Be on the lookout for…
Did the leaves change color?
What day did you notice a color change?
Did both leaves look the same when you took off the foil?
What do you think would happen if you left the foil on longer?