Division where the remainder is the answer, not an error.
Long Division on this site deliberately has no remainders, because "how many 3s fit into 2" is its own idea and belongs in its own lesson. This game is that lesson made playable: divide under a clock and the leftover is what you are racing to name. A student who has only ever seen clean division freezes the first time one does not come out even.
It follows the Long Division lesson. That lesson is live now.