Chasing Light

Safety Note

Please be careful when working with sharp objects like knives and scissors. 

Activity Description

Option A: Visit a sunflower field

• Observe the sunflowers or take pictures of them at different times of the day. What do you see?

Option B: Grow your own plant

1. Cut a 5 cm x 5 cm hole in the upper side of the cardboard box or build a more complex box as shown in the cover photo of this activity.
2. Plant a sunflower seed or a bean seedling in a small flower pot.
3. Place the flower pot inside the box, at the bottom. Make sure that the plant has enough water to grow.
4. Close the box and make sure that there is no light coming into the box except from the hole you cut.
5. Put the box in a place where there is daylight.
6. After a few days, you can open the box and see what has happened to the plant.
7. Analyse what you see: Which way has the plant been growing? Where are the biggest leaves? What was the influence of the obstacles (if you chose to use a more complex box)?

After you finish

• Once you have finished the experiment, you can plant the sunflower or bean plant in your garden or keep it in the flowerpot in your place. Water it from time to time and make sure it gets enough sunlight.  

Evaluation

Understand why many plants grow towards the sun. In your immediate surrounding, can you see an example of this? Of a plant that is growing toward the sun, that has flowers/leaves mainly on one side, that is not growing straight up but towards one side?

Theory

• In order to grow and to thrive, a plant needs basically two things: Water and sunlight.
• In the (almost always) green leaves of the plant, there are small cells that turn water and carbon dioxide (CO2) from the air into oxygen (which we need for breathing) and other substances which the plant needs for building leaves, branches, flowers etc. To do so, these cells need sunlight. This process is called photosynthesis.

Reflection Questions

1. What would happen if there would be no more plants doing photosynthesis and “cleaning the air”?
2. How do parks with trees and many green plants influence the temperature in hot cities?

Make sure that the hole in the upper side of the box is big enough and the circuit is not too complicated, to make sure that the plant gets at least the minimal amount of light to grow. 

In this activity, the participants will learn about the importance of plants doing photosynthesis and “cleaning the air”. You can use this to emphasise the importance of protecting plants,  planting trees etc, within their immediate circles to help protect the climate. Why not ask your school for a school garden?