01 / UNDERSTAND
Your design brief
Design an open card tray for a small collection of classroom objects. Start with an 80 × 60 mm base and 25 mm walls, then revise it to suit the objects you measured.
What you will learn
- Relate a flat net to its folded form.
- Distinguish cut lines from fold lines.
- Use a prototype to make an evidence-based dimensional change.
You will need: Forma, paper or thin card, ruler, a printer and teacher-approved joining/cutting tools. Screen-only learners can annotate a printed net or discuss a teacher-made model.
02 / EXPLORE
Make it in Forma
Menu names refer to the current browser edition. On a touchscreen, use Properties to show the inspector. A keyboard is helpful for exact dimensions.
Measure the contents
Choose a few classroom objects. Record their bounding dimensions and discuss access: can a user pick them up easily? Sketch the tray before generating it.
Check: Record why the starting dimensions might need to change.
Open the wizard
Save current work. Start a new drawing, set millimetres and scale 1:1, then choose Draw → Design wizards → Folded box net.
Check: This is the thin-card net, not the rigid tabbed tray.
Set the first version
Enter Base width 80, Base depth 60, Wall height 25 and Glue / tuck tab width 10. Turn off Include hinged lid. Inspect the preview and choose Add to drawing.
Check: Identify the base, four walls and glue tabs before adding it.
Read the line types
Inspect the Layers panel. The wizard creates CUT and SCORE layers: red for cutting, blue for folds. Keep both visible for the paper model.
Check: Colour names describe the design intention; they do not set machine power or speed.
Make a paper prototype
Choose File → Print / PDF. Use actual size / 100% in the print dialog. Check the printed base with a ruler before assembling it. Fold and join the teacher-approved paper model.
Check: The base should measure 80 × 60 mm; a “fit to page” print may change it.
Test with the user
Place the intended objects in the tray. Ask a partner to remove and replace them. Check access, tab overlap and the usefulness of the wall height.
Check: Record an observation, not just “it works”.
Revise the dimensions
Save version 1. Use a fresh drawing for version 2 and generate a revised net. Make a second paper model if time allows. Compare the result with your original requirements.
Check: Changing the CAD dimensions is only an improvement if the user’s task becomes easier.
03 / REFLECT
Check the design. Explain the decisions.
These ticks are temporary and are not submitted or saved. Keep your project file and written reflection as evidence.
Your design reflection
What did the physical model reveal that the screen did not?
Which dimension did you change and how did you test it?
A little support
Start with a teacher-printed net. Label each panel and fold it before attempting the wizard.
Take it further
Estimate the nominal volume and compare the material used by two designs. Discuss how card thickness and tabs change the usable interior.
FOR TEACHERS
Plan the learning, not just the clicks.
Lesson 1: 10 minutes measurement, 20 CAD and 20 paper prototyping. Lesson 2: testing, revision and comparison. This wizard assumes thin card; it is not a thickness-compensated rigid box. A paper model is sufficient for the activity. Follow local workshop procedures for any later manufacture.
Evidence to look for
Measured contents, the net, a paper model or annotated model photograph, and a reasoned dimensional revision.
Suggested curriculum connection
England KS3 Design/Make/Evaluate: model proposals, select materials and test a prototype against user requirements. Read the England D&T programme.
For other UK nations, use the curriculum adaptation guide. Ages and timings are suggestions, not equivalences between national stages.
Teacher discussion notes
The nominal rectangular volume is 80 × 60 × 25 = 120,000 mm³, or 120 cm³. This ignores card thickness, joints and the clearance needed to remove objects.
Original Forma2D activity · Specialised Laser Systems · Reviewed 5 October 2026
Keep .forma files for editing. Any manufacture uses the school’s approved materials, equipment and procedures.