This is a game for two players. You will need 16 objects, like matchsticks or counters. Set the objects out in a row of 7, a row of 5, a row of 3 and a row of just 1.
Players take turns in a choosing a row then removing any number of objects from that row.
The player left with the last object is the loser. Try playing it with a different number of objects. Try playing it with a different number of rows.