Prerequisite order cards
Arrange tasks in an order respecting every prerequisite, while recognising that several orders can work.
Adult planning suggestion: about 9–12 · Logic & rule checking · Cooperation & communication
- Players
- Teams of three
- Time
- 12–18 minutes
- Materials and quantities
- Per team: six fictional task cards A–F, six prerequisite arrows, order log. No cutting activity is performed by pupils.
30 pupils: ten teams of three; each receives the same graph, then compares two valid orders.
Prepare
Cards describe a pretend display: A fold paper, B draw shape, C adult cuts shape, D attach shape, E write title, F display. Arrows A→B, B→C, C→D, A→E, D→F, E→F mean the left task must be earlier. No real cutting is needed; C is an adult’s task in any later craft use.
Play
Choose an unplaced card whose incoming prerequisites are all already placed. Write it next in the order, then choose another. Cards without an arrow between them need not keep alphabetical order. Do not remove a difficult arrow or perform a task before its prerequisites to make progress.
Example
A,B,C,D,E,F is valid; so is A,E,B,C,D,F. A,B,F,C,D,E is invalid because F appears before both required D and E. A→B does not mean A must be immediately next to B; other ready tasks may occur between them.
Finish
Use every card once, then check all six arrows against positions in the recorded order. Multiple valid orders count. If a different teacher-made set contains a directed cycle, no complete prerequisite-respecting order exists; stop and identify the cycle instead of forcing a solution.
Adapt
Use task pictures with adult reading of arrows and place completed cards in a long row. One pupil proposes, one checks incoming arrows, one records. The supplied set is acyclic; pupils do not have to diagnose an unknown graph before the first attempt.
Aim: Arrange tasks in an order respecting every prerequisite, while recognising that several orders can work.
Practice within this activity: Separating prerequisite from immediate adjacency, checking all arrows and sharing a decision.
Adult observation: Ask why E may be placed before or after B, but F must wait for both D and E.
Mechanism and adaptation: Our version uses topological ordering of directed prerequisites. Examples and print materials are separately written; the earliest inventor is not established here.
Reference checked 24 October 2026: University of Central Florida · Topological Sort — Computing background: order items under directed dependencies; cycles can prevent an order. This university lecture is not a primary-school lesson or age-fit endorsement.
Goals describe observable activity choices, not measured long-term gains or institutional endorsement.
Free alternatives: Write task letters and arrows on large recycled cards; simulate with cards only.
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 fictional task cards
Only simulate with cards. No pupil cutting is required.
Player arrows and order log
Must be earlier, not necessarily immediately before: A→B, B→C, C→D, A→E, D→F, E→F.
| Position | Task | Prerequisites already placed? |
|---|---|---|
| 1 | ____ | ________ |
| 2 | ____ | ________ |
| 3 | ____ | ________ |
| 4 | ____ | ________ |
| 5 | ____ | ________ |
| 6 | ____ | ________ |
Teacher instructions and checked example · separate
30 pupils: ten teams of three; each receives the same graph, then compares two valid orders.
Per team: six fictional task cards A–F, six prerequisite arrows, order log. No cutting activity is performed by pupils.
Write task letters and arrows on large recycled cards; simulate with cards only.
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.
A B C D E F and A E B C D F are both valid. A B F C D E is invalid because D and E must precede F. Check six arrows. The supplied graph has no directed cycle; a different cyclic graph has no full order.