Snowy Boots at the Skate House
In a snowy town, people change into skates at the skate house beside an outdoor rink. Their boots leave puddles by the door. Anika's class wants to plan an entry mat. Its top must hold at least four spoonfuls of water and stay in one piece. Its bottom must stay in place on the wet floor.
The class tests equal-sized squares of paper towel, towel cloth, felt, and rubber sheet. For the water test, they use the same spoon. They add water slowly, up to six spoonfuls per square. They count how many spoonfuls each square holds without dripping when lifted.
Next, they rub fresh squares ten times with the same smooth block, using the same push. They check for tears. For the sliding test, they put fresh squares on the same wet tray. They place the same block on each square and raise one end of the tray to the same mark. They watch for sliding.