Plants Around Us
Primary 2 · Science and Elementary Technology
Plants Around Us
Lesson 3 of 3
15 min
Let's begin
Today you stop reading about plants. Today you grow one.
You need one bean from the kitchen, one old cup or tin, a little soil, a little water, and ten days of patience.
By the end, you will have done what real scientists do: you will have watched something closely, day after day, and written down exactly what happened.
Three small things, every single day:
To record means to write down what really happened — not what you hoped would happen. If nothing happened, you write "nothing happened". That is a real result too!
Write three things each day:
And if you can, draw a small picture. A scientist's drawings are gold.
Ishimwe planted his bean on a Monday. Here is his real page:
| Day | Height | What I saw |
|---|---|---|
| 1 | 0 cm | I planted the bean and watered it. Nothing above the soil. |
| 2 | 0 cm | Nothing yet. The soil is still damp, so I did not water it. |
| 3 | 0 cm | Still nothing! I wanted to dig it up, but I did not. I waited. |
| 4 | 1 cm | A green hook pushed up out of the soil! It is bent over like an elbow. |
| 5 | 3 cm | The hook stood up straight. Two thick leaves opened at the top. |
| 6 | 4 cm | The two leaves turned from pale to dark green. The stem is thin. |
| 8 | 8 cm | Much taller. Two NEW leaves grew, and they are a different shape. |
| 10 | 12 cm | Six leaves now. The whole plant is leaning towards the window. |
Read his table again slowly. It is full of answers.
Roots come first. For three whole days, nothing showed above the soil. But under the soil, the bean was drinking water, swelling up, splitting its skin, and pushing a root downwards. A plant builds its root first, so it can drink. Then it sends a shoot up.
It grew fast. On Day 4 it was 1 cm. On Day 10 it was 12 cm. So it grew 12 - 1 = 11 cm in six days. That is faster than you grow!
It leaned towards the window. Why? It was reaching for the light — just like you learned in the last lesson. So Ishimwe turned the cup around. Two days later the plant had straightened itself up again. He had proved that plants reach for light.
Plant TWO cups on the same day, exactly the same way. Then keep one on the windowsill and one in a dark cupboard. Water them both the same.
You have changed only one thing: the light. So whatever happens differently is caused by the light. Write down both plants every day, side by side.
Do not be sad, and do not think you failed. Real scientists' experiments fail all the time. What a scientist does next is ask why:
Then you fix that one thing and try again. Asking "why did it not work?" IS the science.
Tip
Visit your plant at the same time every day — right after breakfast is easy to remember.
And write it down straight away, before you run off to play. A memory fades by lunchtime. A notebook never forgets.
Work each one out first. The answer is right underneath.
Umutoni's bean was 3 cm tall on Day 5. On Day 9 it was 9 cm tall. How many cm did it grow?
Answer: 9 − 3 = 6 cm.
It is Day 3 and Byiringiro can see nothing above the soil. He wants to dig the bean up and look at it. Should he?
Answer: no! Digging would break the tiny new root. Beans often take 4 or 5 days to show. He should keep the soil damp and wait.
Mutesi's plant is leaning right over towards the window. What is it reaching for, and what can she do?
Answer: it is reaching for the light. She can turn the cup around, and in a day or two the plant will straighten up.
Habimana wants to test if his bean needs light. He puts one cup in the sun and one in a dark box. What must he keep the same for both cups?
Answer: everything else — the same soil, the same water, the same kind of bean, the same size cup. Only the light is allowed to be different.
On Day 2, nothing has happened. What should Ishimwe write in his notebook?
Answer: he should write "Day 2: nothing above the soil yet." A scientist writes down what really happened, even when the answer is "nothing".
Note
What you learned today:
Quick check
Day 3. Nothing shows yet. What do you do?
