Seed Bombs Grow Ideas

Overview

Students build a seed bomb during Science Week to learn how to design a fair, safe investigation about seed germination and conditions for growth. The lesson links the Science understanding of living things to practical planning, controlled testing, safe use of materials, and communicating findings.

Learning intentions

• Students will use the engineering/design process to make a seed bomb safely and accurately.
• Students will identify a test question about seed germination and growth conditions.
• Students will plan a fair test by deciding variables to change, measure and control.
• Students will record observations and share results using scientific language and simple data displays.

Success criteria

• I can describe what my seed bomb contains and why (seeds + growth medium + protective binder).
• I can name the variable I am changing, the variable I am measuring, and other factors I will keep the same.
• I can follow safety rules when using soil/compost, tools and water.
• I can communicate my investigation plan and early observations clearly (oral, written or digital).

Curriculum links

• AC9S6I02 — plan and conduct repeatable investigations, including deciding variables (changed/measured/controlled), fair testing, risks, and permissions to investigate on Country/Place.
• AC9S6I06 — write/create texts to communicate ideas and findings for a purpose and audience, selecting language features and using digital tools as appropriate.
• Science as a Human Endeavour: using scientific ideas and methods to solve a practical problem (growing plants responsibly).

Lesson structure (60 minutes)

1. 0–5 min · Science Week hook. Teacher shows images of seed bombs/garden growth and asks, “What conditions help seeds grow, and how can we test this fairly?” Students share quick ideas with a partner.

2. 5–12 min · Mini-lesson: living things need conditions. Teacher explains that seeds need water and suitable conditions to germinate, linking to respectful land care and sustainability (no littering, only use prepared materials). Students do a quick “conditions sort” (cards: water, sunlight, temperature, space, soil/medium).

3. 12–18 min · Safety and roles. Teacher runs a short risk check: clean handling of compost/soil, hygiene (wash hands), safe tool use (if any), and controlled water. Students choose roles (materials manager, mixer, modeller, recorder) and state one safety rule.

4. 18–35 min · Make the seed bomb (design + craft). Teacher demonstrates mixing seed-bomb material (seeds + compost/soil/peat substitute + binder) and forming consistent balls; checks mixture consistency and size for reliability. Students make seed bombs in groups, using a simple “design checklist” (same scoop size, mix thoroughly, form to similar diameter).

5. 35–45 min · Turn craft into investigation plan (fair test). Teacher provides 2–3 investigation options with students selecting one as a class (e.g., “Does extra water change germination rate?” or “Does more light change growth?”). Teacher models a table: variable changed / variable measured / variables controlled. Students complete the table for their chosen option using sentence starters.

6. 45–55 min · Record and predict. Teacher prompts a brief prediction: “What do you expect to happen, and why?” Students add a prediction and expected measurement (e.g., “number of sprouts after 7 days” / “height after 2 weeks”) to their science notebook or class template; teacher collects examples.

7. 55–60 min · Share-out + exit check. Teacher calls for two groups to explain their variable choices and one safety rule. Students complete a 1-minute exit check: “My changed variable is…, my measured variable is…, I will keep… the same.”

Resources

• Seed bomb materials prepared in advance: seeds (fast germinating for this age range), compost/soil, binder (e.g., clay-based or compost-based mix), small scoops/measuring cups
• Water in controlled pour jugs or squeeze bottles; buckets/trays for mixing
• Disposable gloves (optional), paper towels, bench protectors
• Writing/recording templates (one page) with variables table + sentence starters
• Science journals or clipboards, markers
• Handwashing supplies and classroom hygiene reminders
• Digital option: a shared slide/doc for predictions and variable choices (one device per group or teacher screen sharing)

Assessment

• Formative during making: teacher checks whether students follow the safety rules and maintain consistent seed-bomb size/mixture (reliability).
• Formative during planning: review variables table for correct identification of changed/measured/controlled variables and reasonable measurement.
• Exit ticket: written or drawn response confirming the three variables and one controlled factor.

Differentiation

• Pre-Primary/Kindergarten–Early Years: teacher provides pre-measured materials; students focus on sequencing steps (mix, scoop, roll) and make an observational “what I notice” drawing. Variables are handled as pictures (changed = “more/less water”, measured = “sprouts yes/no”).
• Years 1–2: students select one simple question (“Will seeds grow with water or without?”) and measure by counting sprouts after a set time; sentence starters support “We will keep…” wording.
• Years 3–4: students write a short fair-test plan with one changed variable and one measured variable, plus two controlled variables (e.g., same amount of soil/seed bomb size).
• Years 5–6: students refine the investigation with clearer operational definitions (how “sprout” will be counted, timing, units) and propose a repeatable method. Students can add a data representation plan (tally chart/graph) and begin a science report introduction.
• Support for all: photo prompts for steps, vocabulary bank (seed, germination, water, sunlight, control, measure), and teacher-conducted modelling before group work.
• Extension (within task choices): groups choose between two investigation options and justify their choice using evidence from the conditions sort activity.