Free / Grades 4-5, with reading and fraction support
Plant Evidence Lab
What can a seed record tell us, and what would be a guess?
4 flexible sessions / about 140 minutes including practice / biology, math, reading and art
Suggested rhythm: two sessions a week for two weeks. Week 1: plant needs and fair comparisons. Week 2: seed records and a revised explanation. Pause or spread sessions out as needed.
Reading, watching and paper activities are free. Parents and instructors can save a collection; scheduling it for a student requires Plus or Lifetime. No upload is required.
Before you begin
Read small tables, subtract whole numbers and compare fractions with the same denominator. Read aloud, point or dictate whenever helpful. The videos introduce plant food-making and the difference between predictions and results.
A paper investigation, not a growing kit. Use the invented records provided. No seeds, soil, chemicals, lamps or growing experiment are required. Do not taste plants or seeds or handle mold. These records are not observations you made. Keep any separate real observations clearly labeled; ask an adult before any real growing activity.
Materials
- 4 sheets per learner: Project journal
Print four pages or copy the headings into a notebook.
- 2 sheets per learner: First and revised explanations
Use clean scrap paper and keep the first version. A spoken explanation is valid.
- 1 per learner: Pencil
Point, dictate or use an accessible writing tool.
- 1 shared, optional: Ruler
Use a paper edge for a table; exact drawing is not needed.
- 1 shared: Browser with audio or transcripts
Read the existing transcripts together. Separate worksheet printing is optional.
Choose the support that fits
- More support: draw eight labeled boxes for each group. Mark a sprout with a symbol as well as color; count before simplifying fractions.
- More challenge: express the final fractions as percentages, then distinguish a percentage-point difference from the number of extra sprouts.
- Access options: describe the plant model, point to table cells or dictate a report. No upload, recording, public presentation or purchase is needed.
What good evidence looks like
- Distinguish light energy, water, carbon dioxide and sugars in a green-plant model.
- Separate a prediction, a recorded observation and an explanation.
- Specify one changed condition, shared conditions and a clear sprout-counting rule.
- Use the original group size and time label; do not count the same sprout twice.
- Keep invented data labeled, name a limit and explain a revision to the first account.
These are discussion criteria, not a new automatic score. Existing lesson and worksheet records keep their own subjects. Checking off a planned task does not demonstrate mastery or add a second grade.
Session 1 / about 35 minutes
A seed is not a tiny sandwich shop
Goal: Connect plant structures with inputs and distinguish stored seed food from later food-making.
Preparation / about 6 minutes of adult support: Have journal 1 and a first-explanation sheet ready. Read the arrows as named jobs, not as a scale drawing. Keep a first explanation for revision in session 4.
In our green-plant model, roots take up water and minerals; stems connect plant parts. Photosynthesis uses water and carbon dioxide, with light energy, to make sugars. Soil is not a supply of ready-made sandwiches. A seed contains a young plant and stored food that can support early growth. Germination means growth resumes; it is not the same event as a mature plant making new seeds. This simple model leaves many cell processes out.
Ask whether light is a material like water or an energy input in this model. Then ask how a sprout can begin growing before it has a large set of leaves.
- A green plant's food factory / about 5 minutes
- A Green Plant Makes Its Food / about 10 minutes
- Keep my first plant explanation / about 20 minutes
Fun fact: Some green stems can carry out photosynthesis too. Leaves are important, but they are not the only possible food-making surface. Source
S3U / Plant Evidence Lab / Journal 1 of 4
Different jobs, different inputs
Use the green-plant model, then write a first explanation of how a seed begins growing and how a green plant makes sugars. Keep your first version even if you are unsure.
| Prompt | My explanation |
|---|---|
| Water: where does it enter the model? | |
| Carbon dioxide: where does it come from? | |
| Light: material or energy? | |
| Stored seed food: what can it support? |
Explain why soil is not the same thing as ready-made food for the plant.
What question about seeds would I want evidence for, rather than guessing?
Session 2 / about 35 minutes
Give the comparison a fair start
Goal: Plan one changed condition, shared conditions and a reproducible counting rule.
Preparation / about 7 minutes of adult support: Have journal 2 ready. The proposed comparison is only on paper. Keep its plan separate from the invented outcome records in session 3.
A prediction comes before a result. To investigate one condition, avoid changing several things together. A separate example compares two groups of six seeds, all from one batch, with the same water, air access and temperature but different light conditions. Define what counts: here a seed counts once when a root is visible at an agreed check. Record the day too. Repetition can show variation; it does not rescue a poorly defined question. A seed cannot fill in a missing label for us.
A pretend plan changes light, water and seed type at once. Ask which change could explain a difference. How could the plan make that question easier to answer?
- Science: let the results have their say / about 5 minutes
- Separate Predictions from Results / about 10 minutes
- Repair the seed comparison plan / about 20 minutes
Fun fact: Seeds need suitable water, oxygen and temperature to germinate. Light requirements differ among kinds of seeds; there is no single light rule for every seed. Source
S3U / Plant Evidence Lab / Journal 2 of 4
One question, a checkable plan
Flawed invented plan: group A has 8 seeds of type X, light and damp paper. Group B has 8 seeds of type Y, darkness and dry paper. Both will be checked on day 6. The question is about light, not seed type or water.
| Part of the plan | My repair or explanation |
|---|---|
| Conditions changed together | |
| One condition to investigate | |
| At least three conditions to keep alike | |
| What counts as a sprout, and when? |
Write a prediction and label it as a prediction, not an observation.
Why would repeating the flawed plan many times still leave a problem?
Session 3 / about 35 minutes
Count sprouts, not repeated appearances
Goal: Read cumulative counts and compare fractions using the original seed totals.
Preparation / about 7 minutes of adult support: Have journal 3 ready. Each group keeps the same eight seeds. A visible-root seed remains counted at later checks; do not add daily totals together.
A cumulative count means how many have met the rule by that check. In a separate five-seed example, the counts are 1 by day 2, 3 by day 4 and 4 by day 6. That is four seeds by day 6, not eight. The final fraction is 4/5; the denominator is the original group, not just the seeds that sprouted. Our project uses different groups of eight. Keep a missing observation distinct from zero. A table records its stated event, not every feature of plant health.
Ask what a blank day-4 cell would mean. Would filling in zero make it an observation? Then ask whether a visible root proves how tall or healthy the plant will be later.
- Calculate the Fraction of Seeds That Sprouted - Practice 1 / about 10 minutes
- Compare the eight-seed records / about 15 minutes
- Read the limits of the record / about 10 minutes
Fun fact: A seed can swell after taking up water without completing germination. A change in appearance and a visible root are different observations. Source
S3U / Plant Evidence Lab / Journal 3 of 4
By this day, out of this group
Invented repaired comparison: 8 seeds per group from one batch; same water, air access and temperature; A in light, B in darkness. Count each seed once after a root is visible. Cumulative A counts: day 2 = 2, day 4 = 5, day 6 = 6. B: day 2 = 1, day 4 = 3, day 6 = 4. These are not your measurements.
| Quantity | Group A | Group B |
|---|---|---|
| Fraction sprouted by day 6 | ||
| Additional sprouts after day 2, by day 6 | ||
| Not sprouted by day 6 |
Compare the final counts and fractions. Why must I not add all three cumulative counts?
Revise this claim: "Every seed needs light, and every seed not sprouted by day 6 is dead."
Session 4 / about 35 minutes
Let the evidence edit the explanation
Goal: Present a bounded plant explanation with labeled evidence and an explained revision.
Preparation / about 8 minutes of adult support: Bring the first explanation, all journals and a new sheet. An available adult can listen or the learner can rehearse privately; nobody is monitoring live.
Build a revised display with a plant-input model and a separate seed-record table. Label the table invented practice data. Include the question, counting rule, day and group size. Explain what the records support, then name what remains unknown. A green-plant model explains useful processes, but it does not prove why any particular seed failed to sprout. Keep the first explanation beside the revision. Your report needs evidence, not a trophy for the tallest imaginary seedling.
Ask a listener to point to the record behind one sentence. If no listener is available, do that check yourself. Replace an always, every or definitely that goes beyond the evidence.
- Draw a labeled plant-and-evidence display / about 15 minutes
- Write a careful seed explanation / about 10 minutes
- Explain my revision and next question / about 10 minutes
Fun fact: Plants use sugars in respiration as well as making them through photosynthesis. Food-making and using stored energy are related but different processes. Source
S3U / Plant Evidence Lab / Journal 4 of 4
My plant explanation and its limits
Keep the first explanation and use another sheet for the revised display. Spoken explanations and labeled tables are valid alternatives to a drawing. Retain the invented-data label.
| Evidence to keep | My explanation |
|---|---|
| One correctly labeled plant input | |
| A day-6 claim with group size | |
| What the records leave unknown | |
| One change from my first explanation |
Which specific observation or model helped me change my explanation? Do not invent a mistake if the first version was already careful.
What further evidence would help answer my next question? This is a proposal, not a claim that I collected it.
What changed in your explanation?
Show your evidence, explain one revision, and choose a question to investigate next. You can keep everything on paper.
Optional: record actual offline learning in Learning Records. Keep reported minutes separate from website time. For an assigned pack, use your existing daily tasks; this page does not award additional completion credit.