Two-set overlap sorting
Place each card by two independent properties: red and circle, including both and neither.
Adult planning suggestion: about 4–6 · Logic & rule checking · Observation & recall · Language & storytelling
- Players
- 4–5 per group
- Time
- 8–12 minutes
- Materials and quantities
- Per group: eight large shape cards and a four-zone mat; two cards for every colour/shape combination, one small and one large.
30 children: six groups of five; one speaker, one mover and three rotating checkers.
Prepare
Use eight cards: red circle, red square, blue circle and blue square, each in a small and large drawing. All physical cards remain large enough for adult-led handling; “small” refers to the printed shape, not a tiny loose piece. Mat zones are red-only, circle-only, both, neither.
Play
Take one card and answer two questions separately: Is it red? Is it a circle? Place it in the one zone matching those answers. Both yes goes in both; both no goes in neither. A card occupies one zone, not one copy in each matching set.
Example
A large red circle belongs in both. A small blue circle belongs in circle-only. Red squares belong in red-only; blue squares in neither. Size changes none of these answers because size is not a rule in this round.
Finish
All eight cards should be placed, two per zone. Count and explain one card from each zone; if a zone has the wrong count, check properties rather than moving cards to force equal totals. After checking, partners may take turns pointing to a requested zone.
Adapt
Adult reads the colour labels and a child points, or a partner moves the card. Do not rely on colour alone. Start with four cards, one per colour/shape combination, explicitly keeping the same two questions.
Aim: Place each card by two independent properties: red and circle, including both and neither.
Practice within this activity: Answering two property questions independently, combining their results and explaining a placement.
Adult observation: Ask whether changing only size would change the zone; look for a reason tied to the stated properties.
Mechanism and adaptation: Our version uses two-property membership with an intersection and exterior. Examples and print materials are separately written; the earliest inventor is not established here.
Reference checked 24 October 2026: University of Cambridge NRICH · Venn Diagrams — Related set-classification mechanism: both conditions, one only, or neither. Source lists ages 5–11; our large shape cards and 4–6 adult suggestion are separate, untested adaptations.
Goals describe observable activity choices, not measured long-term gains or institutional endorsement.
Free alternatives: Hand-draw eight large red/blue circles/squares on recycled card; label colours as words too.
Buying recommendations reserved; no purchase required.
Printable materials
Preview at 100% scale, with browser headers and footers off. Cut with suitable help. Keep host keys separate. This is a manual tabletop kit, not an online opponent, automatic judge or solver.
Player four-zone mat
| Red only | Both red AND circle |
|---|---|
| ________________ | ________________ |
| ________________ | ________________ |
| Circle only | Neither red nor circle |
|---|---|
| ________________ | ________________ |
| ________________ | ________________ |
Size does not affect the zone. One card occupies one zone.
Player eight large property cards
Adult cuts the outer card borders. All physical cards remain large; small/large describes the pictured shape only.
Teacher instructions and checked example · separate
30 children: six groups of five; one speaker, one mover and three rotating checkers.
Per group: eight large shape cards and a four-zone mat; two cards for every colour/shape combination, one small and one large.
Hand-draw eight large red/blue circles/squares on recycled card; label colours as words too.
Print only the relevant player pages; keep this teacher page separate. Read the full web rules before leading. A helper may write or move pieces, and anyone may pause or pass. No classroom or physical-printer trial is claimed.
| Zone | Cards |
|---|---|
| Red only | Both red squares |
| Circle only | Both blue circles |
| Both | Both red circles |
| Neither | Both blue squares |