What You'll Need

Corrugated cardboard sheet or shoe box
Craft knife / scissors & hot glue
Thick yarn, jute or shoelace (≈ 60 cm)
Two beads (fit through ring) + two cardboard squares (larger than ring)
Ruler, pencil & hole punch

Safety First!

!Supervise hot glue, craft knives and 3D-printer hot end.
!Sand any sharp 3D prints before play.
!Use child-safe, non-toxic paint or markers if decorating.
!Keep beads away from children under 3 years.
!Tie secure knots; loose parts pose choking hazards.

Let's Make It! Step-by-Step Guide

Model / Measure

Step 1 of 5

Download the STL files, or draw on cardboard a post roughly 12 cm tall with a base measuring 8 cm × 8 cm.

The Science Behind It

Disentanglement puzzles train spatial reasoning and sequential logic: solvers must visualise the cord as a continuous path, predict its behaviour and plan moves in advance. Physically looping cord over the post also refines fine-motor coordination and bilateral hand use, echoing early knot-tying and lacing skills that later support handwriting.

Helpful Tips

Use contrasting colours for ring vs. cord to highlight the path.
Stiffen flimsy yarn with a light coat of PVA glue; prevents fraying while still flexible.
Knot too fat to fit through the ring? Wrap tape around the cord end while threading.
Print two rings in different sizes: easier (large) vs. trickier (tight clearance).
Record a time-trial leaderboard to keep kids engaged.

Try These Variations!

1Dual-Ring Challenge: Add a second ring—must free both without detaching the cord.
2Math Mode: Mark moves 1-6 on the post; require players to announce the numbered step they’re on (reinforces ordinal counting).
3Glow Edition: Print in phosphorescent filament for low-light “camp-out” play.
4
5Magnetic Squares: Embed tiny magnets in the blocks so they “click” to the base when solved.
6Story Quest: Paint the ring as a “dragon portal,” squares as “gate stones,” then role-play freeing the realm!

Removing Ring Brain Teaser