How much water do bean seeds need to sprout?
- 👶 Small parts
- 🧼 Wash your hands after
My hypothesis
If I change how much water the beans get each day, then how many of the five beans sprout in ten days will ______, because ______.
You fill in the blanks. Think about what a dry seed is waiting for, and what else a seed needs besides water. A guess is a good because: the test finds out.
Change, measure, keep the same
CHANGE
how much water the beans get each day: None, A little (1 teaspoon), Medium (1 tablespoon), Lots (3 tablespoons)
MEASURE
how many of the five beans sprout in ten days, in beans sprouted, of 5
KEEP THE SAME
- the same kind of bean
- five beans in every bag
- the same warm room, out of direct sun
Scientists call the thing you change the independent variable and the thing you measure the dependent variable. The things you keep the same are the controls: if one of them changed too, you wouldn't know which change made the difference. Try each of the 4 levels 3 times.
What you need
- Dried beans from the grocery bag (pinto, lima or kidney): 60, all the same kind
- Paper towels
- Plastic bags: 12 zip bags
- Measuring spoons
- Water from the tap
- Masking tape, to mark lines
- Crayons or markers
Steps
- Fold a paper towel into each of twelve zip bags.
- Label three bags none, three a little, three medium and three lots.
- Put five beans in each bag, on top of the towel.
- Water each bag its own amount, and zip it almost shut.
- Tape the bags to a wall in a warm room, out of direct sun.
- Every day, add the same water and count the beans that have sprouted.
- On day ten, write the final count for each bag in your table.
- Draw a bar graph of beans sprouted for each amount of water.
- Wash your hands after handling the beans.
Every step is one you can do yourself, with a grown-up nearby. Write each number down straight away, in the table below, so nothing is lost.
Your results table
Name ______________________ Fair day ____________
Question: How much water do bean seeds need to sprout?
I changed: Water each day I measured: how many of the five beans sprout in ten days (beans sprouted, of 5)
| Water each day | Try 1 (beans sprouted, of 5) | Try 2 (beans sprouted, of 5) | Try 3 (beans sprouted, of 5) | Mean |
|---|---|---|---|---|
| None | ||||
| A little (1 teaspoon) | ||||
| Medium (1 tablespoon) | ||||
| Lots (3 tablespoons) |
MY GRAPH (a bar graph: water each day along the bottom, beans sprouted, of 5 up the side)
What I noticed: ______________________________________________
From 4th grade, add the tries for each level and divide by how many there were: that's the mean, and it goes in the last column. Then draw a bar graph, one bar for each thing you tried.
Name ______________________ Fair day ____________
Question: How much water do bean seeds need to sprout?
If I change how much water the beans get each day, then how many of the five beans sprout in ten days will ________________, because _____________________________________________
| I CHANGE | I MEASURE | I KEEP THE SAME |
|---|---|---|
| Water each day: None, A little (1 teaspoon), Medium (1 tablespoon), Lots (3 tablespoons) | how many of the five beans sprout in ten days (beans sprouted, of 5) |
|
What I think will happen, in my own words:
Name ______________________ Fair day ____________
Question: How much water do bean seeds need to sprout?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: How much water do bean seeds need to sprout?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: How much water do bean seeds need to sprout?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: How much water do bean seeds need to sprout?
My hypothesis was ☐ right ☐ partly right ☐ not right.
I know because my numbers show:
What surprised me, or what might have gone wrong (7th and up):
Next time I would test:
Idea: Change a second thing: measure the longest root every day, and draw a line for each amount of water.
Why it works
A bean seed is a tiny plant packed up with food, waiting for water to wake it. Water soaks in, the seed swells, and a root pushes out. With no water it stays asleep, and too much water can keep air away from it, so the middle amounts often do best.
Going further (7th and up): Change a second thing: measure the longest root every day, and draw a line for each amount of water.
Board layout
- ❓ Question (10 × 8 in): How much water do bean seeds need to sprout?
- 💭 Hypothesis (10 × 9 in): If I change how much water the beans get each day, then how many of the five beans sprout in ten days will ______, because ______.
- 🧺 Materials (10 × 12 in): 7 things: see your list.
- 🪜 Steps (22 × 9 in): 9 steps, three tries at each level.
- 📊 Results (22 × 16 in): Your table (Water each day down the side, tries across) and your bar graph.
- ✅ Conclusion (10 × 14 in): My hypothesis was right / partly right / not right. I know because…
Materials to list: Dried beans from the grocery bag (pinto, lima or kidney); Paper towels; Plastic bags; Measuring spoons; Water from the tap; Masking tape, to mark lines; Crayons or markers.
Bring photos or drawings of your test. Nothing wet, hot, powered or alive on the table.
This project at your grade
| 1st–3rd grade | Tries: three at each level (one is fine at a first fair). The table: levels and tries, numbers or pictures. The graph: a picture, or a simple bar graph. The conclusion: what happened, in their words. |
|---|---|
| 4th–6th grade | Tries: three at each level. The table: units in the header and a mean column. The graph: a bar graph, or a line for a number that grows. The conclusion: right, partly or not, and the numbers that show it. |
From 4th grade up, the table gets a mean column. See every project for 2nd grade, or print a blank results table.
What a judge will ask
- What did you change, and what did you measure? I changed how much water the beans get each day and measured how many of the five beans sprout in ten days, in beans sprouted, of 5.
- What did you keep the same, and why does that matter? I kept the same kind of bean and five beans in every bag the same, so the only difference was how much water the beans get each day.
- How many times did you test it? 3 times at each of my 4 levels.
- If you did it again, what would you change or test next? I'd measure the longest root every day, and draw a line for each amount of water.
Make it yours
Keep this project on this device and Peabody counts down to your fair day, with a plan for each day. Nothing is sent anywhere.
Try next
👨👩👧 For grown-ups and teachers: how much to help, the safety rules, and running a school fair. Science fair v0.16.1 · Checked .