Technologies K–10 · Years 1–2
Repeat loops in a bead bracelet
Design and Production (NSW Science and Technology K–6, 2017) (algorithms); Digital Technologies: Processes and production skills, Generating and designing (ACARA v9)
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The idea
A repeat instruction (iteration) makes a short list of steps produce a long pattern, so 'repeat 5 times: red, red, blue' threads 15 beads.
What you need
- 30 red, 15 blue, 10 yellow and 30 green pony beads per pair (both partners threading cards 1 and 2 use 20 red, 10 blue, 8 yellow and 24 green, leaving beads for step 6)
- 1 pipe cleaner or 40 cm of cord per bracelet
- Algorithm card 1: 'repeat 5 times: red, red, blue'
- Algorithm card 2: 'repeat 4 times: yellow, then repeat 3 times: green'
- Recording sheet with columns for predicted and counted beads
How to do it
- Read card 1 aloud and point to each step as it is said.
- Before threading, predict how many red and how many blue beads you will need and write the numbers down.
- Thread the beads while saying each step. Make a tally mark each time the group of three is finished.
- Count the beads of each colour and compare with the prediction.
- Read card 2, where one repeat sits inside another. Predict the counts again, then thread and check.
- Write a new algorithm card for a partner, predict their bead counts, then check their bracelet.
What you should see
Card 1 gives 15 beads: 10 red and 5 blue, ending in blue. Card 2 gives 16 beads: 4 yellow and 12 green, each yellow followed by three greens. The learner knows the algorithm was followed when the counts match the prediction; a card 1 bracelet with 14 or 16 beads shows a skipped or extra step, a bug found by checking the bracelet one group at a time.
What changes
This activity lists no variables to change, measure and keep the same.
Common misconceptions
Each of these ideas is wrong, and the activity is a chance to test it.
- A repeat repeats only the last step (it repeats the whole group inside it).
- Repeat 4 times with repeat 3 times inside makes 7 greens (a repeat inside a repeat multiplies: 4 × 3 = 12).
- An algorithm has to be typed into a computer (a bead card is an algorithm that people follow).
Safety card
Hazards
- Small beads are a choking hazard
Controls
- Beads stay in trays on the table and are counted back in
Note
No chemicals or heat. Record the activity on Primary School RiskAssess (riskassess.com.au).
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. The syllabus taught in 2026; the 2024 syllabus replaces it from 2027. Code read from the official syllabus document (DOCX) on 2026-09-22.ST1-3DP-T
- 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-DDT-01
- Australian Curriculum v9AC9TDI2P02
Sources
The pages the author read to write this activity.