← All lesson plans
Full access Engineering and structuresArt and pattern

Sorting step by step

Make five separate PLA strips with the same width and different lengths. Propose a repeated action that will sort a shuffled set from shortest to longest. Record your idea, test it and explain it to your partner.

Age
8–10 years
Length
approx. 45 min
Level
Easy
Where you teach
School
Purpose
Educational
Choose a plan in the shop Enter a code

How to run this session

Stages and timing
  1. The two longest strips
  2. First comparison
  3. Three shorter strips
  4. Remove, count and put away the template
  5. First I discover my rule
  6. I test the method in five rounds
  7. Recording my procedure and checking with a ruler
  8. New arrangement and cleanup
  9. Optional: the same rule, descending

What gets built

The pupil makes five separate PLA strips (30, 40, 50, 60 and 70 mm), proposes a repeated action for sorting by length, carries out and describes the procedure, and tests it on a new arrangement without omitting elements.

What it practises
  • Tracing a single PLA layer along the centre of the template line and comparing lengths at a common starting line.
  • Distinguishing comparison from measurement. Recording a repeated action as a short procedure with a return to an earlier step.
  • Testing a personal rule on a new, shuffled arrangement.

Success criteria
  • The model is complete: five separate PLA strips of increasing length with no connections between them.
  • The sheet records the number of strips before selection in each round; no item was omitted.
  • Five marks at the starting line form rising steps.
  • The pupil independently completed the selection rule, placement and return number in the procedure.
  • The second sort records the number of rounds and whether any strip was omitted.

What you need
Filament
PLA
Colours
colour shown in the illustration
Also
3D pen for PLA: 1 per pupil., Pen power supply: 1 per pupil., Transparent work mat resistant to PLA working temperature: 1 per pupil., 1:1 template for five strips (sheet EINF05-PASMA): 1 per pupil., Procedure sheet: 1 per pupil., Blank A4 sheet: 1 per pupil., Pencil: 1 per pupil., Ruler: 1 per pupil., Named envelope: 1 per pupil., Pen stand: 1 per pupil.

Files

The files for this plan are part of full access

Anyone can read the description. The slides, instructions and worksheet open with full access to the Creators Club. Choose a plan in the shop, then enter the code from the email in your account. Access starts when you enter the code.

Choose a plan in the shop Enter a code

How did the session go?

Your rating and notes come to us only. We do not publish them; we use them to improve the plans.

Rate it school-style, from 1 to 6.

Version a2e37463-6d4f-46b6-b739-9ef81d0f2e4b Updated 2026-10-14

Write to us