Today we are going to plant seeds and watch them grow. This is called a growing experiment. We will plant the same kind of seed in two cups.
Cup One will sit by a sunny window. Cup Two will sit in a dark closet. We want to find out if plants need sunlight to grow. We will water both cups the same amount every day.
Over the next week, we will check our seeds every day. We will measure how tall the sprouts are. We will draw pictures of what we see. At the end of the week, we will compare the two plants and see what sunlight did.
1. What do you think will happen to the seed in the sunny cup?
2. What do you think will happen to the seed in the dark cup?
3. Why are we watering both cups the same amount?
What you need: 2 clear cups, potting soil, 2 seeds, water, a ruler
Step 1: Fill both cups with soil, leaving 1 inch of space at the top.
Step 2: Make a small hole about 1/2 inch deep in each cup. Drop one seed in each hole and cover with soil.
Step 3: Water each cup with 2 tablespoons of water.
Step 4: Put Cup One by a sunny window. Put Cup Two in a dark place.
Step 5: Check and water both cups every day at the same time.
⚠️ Safety: Ask a grown-up to help you get the soil. Do not eat the seeds or soil. Wash your hands after planting. Keep soil off the floor so no one slips.
Check your seeds every day and record what you see.
| Day | Cup 1 (Sunny) — What I See | Cup 2 (Dark) — What I See | Cup 1 Height (cm) |
|---|---|---|---|
| Day 1 | |||
| Day 2 | |||
| Day 3 | |||
| Day 4 | |||
| Day 5 | |||
| Day 6 | |||
| Day 7 |
Day 1
Day 3
Day 5
Day 7 — Sunny Cup
Day 7 — Dark Cup
Compare Side by Side
| Question | Cup 1 (Sunny) | Cup 2 (Dark) |
|---|---|---|
| Did it sprout? | ||
| How tall is it? | ||
| What color is it? | ||
| Does it have leaves? | ||
| Is it standing up straight? |
1. Which plant grew better? Why do you think that happened?
2. What was the biggest difference between the two cups?
3. Do plants need sunlight? Use your observations to prove your answer.
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Draw your ideal growing setup and label what you are giving the plant:
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