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Players pass cards to other team members in order to help one another complete their set.
Use an observer to check that the team obeys the rules and to keep a record of when members of the team help someone else (rather than, for example, when they just pass a piece on without looking at what the other person or the team actually needs).
Account of an investigation which starts from the area of an annulus and leads to the formula for the difference of two squares.
An algebra task which depends on members of the group noticing the needs of others and responding.