Science and Technology K–6 · Years 1–2
Mealworms: watching a life cycle
Living World, living things change (NSW 2017); Science inquiry (ACARA v9)
The idea
An animal changes form as it grows, and the stages happen in a fixed order that can be recorded over weeks.
Safety card
Hazards
- Allergy to insect dust; escape of a non-native beetle
Controls
- Tubs opened by the adult; lids ventilated but secure; colony never released outdoors
Note
Live animals: the 2017 syllabus Animal Welfare section and the NSW Department of Education science safety and compliance page (which points to the Animals in Schools site) apply. Mealworms are bought, not collected: keep the colony or hand it on, and never release it outdoors. Record the activity on Primary School RiskAssess (riskassess.com.au).
What you need
- 20 mealworms (larvae of the darkling beetle) from a pet shop
- Two ventilated tubs with 3 cm of wheat bran, a slice of carrot for moisture, replaced twice a week
- A hand lens; a ruler; a weekly class chart with columns: larvae, pupae, beetles, and the length of the longest larva
- One tub in the warm classroom and one in a cooler room (a thermometer beside each)
How to do it
- Predict which tub will show pupae and beetles first.
- Count the larvae in each tub and measure the longest one on day 1. Record both temperatures.
- Each week count larvae, pupae and beetles in each tub, measure the longest larva, and draw one animal of each stage present.
- Replace the carrot twice a week; do not handle the pupae.
- When beetles appear, record the week. Compare the warm tub with the cool tub and with the prediction.
- At the end of term keep the colony or hand it on; do not release it outdoors.
What you should see
Larvae grow and shed their skins (shed skins appear in the bran), then turn into pale, curled pupae that do not eat, and each pupa becomes a beetle that is pale at first and darkens over a few days; the order larva, pupa, beetle never varies. When the two thermometers show a clear difference, the warm tub is expected to reach the pupa and beetle stages first. The number of weeks is the class result; it depends on the temperatures the chart records, and the cool tub may not reach beetles within a term. The learner knows it worked when the chart shows pupae appearing before beetles in every tub that reaches beetles.
What changes
- What you change
- temperature of the room (warm or cool tub)
- What you measure
- week each stage first appears; length of the longest larva (mm)
- What you keep the same
- same bran and carrot
- same starting count
- same weekly count day
Common misconceptions
Each of these ideas is wrong, and the activity is a chance to test it.
- Mealworms are worms (they are beetle larvae).
- A pupa is dead because it does not move.
Curriculum references
The NSW syllabus outcomes and Australian Curriculum v9 codes this activity supports. They are references, not a verified or complete curriculum alignment.
- Science and Technology K-6 Syllabus (2017), NESA. Current syllabus; NESA's timeline is 2026 plan and prepare, 2027 start teaching the 2024 syllabus. Code read from the official syllabus document on 2026-09-22.ST1-4LW-SST1-1WS-S
- Science and Technology K-6 Syllabus (2024), NESA. Implementation from 2027, so this code describes the future syllabus. Code read from the outcomes page on 2026-09-22.ST1-SCI-01ST1-DAT-01
- Australian Curriculum v9AC9S2I01AC9S2I02AC9S2I03AC9S2I04AC9S2I06
Sources
The pages the author read to write this activity.