A school forms whenever 3 or more young share the same slot in your ocean. When this occurs, immediately return 3 young from that slot to the supply and replace them with 1 school token (shown as this icon in the game:
).
• You may never have more than 1 school in the same slot. If you have 3 or more young in a slot with a school, nothing happens.
• If you have 3 or more young in a slot with a school and then move that school, 3 of those young immediately form another school where they are.
• If you attempt to move a young through a slot that has 2 young in it (and no school), a school will form (and that move will end).
• A school may not enter or move through a slot that already has a school in it.
Schools are worth 6 points each at the end of the game (as opposed to young, which are only worth 1 point each). Once a school has been formed, it may not be broken up into individual young again.