Split the class in to two groups.
Write up four columns with A, B, C, D on either side of the board.
Call out a topic like Country, Food, Animal, etc. Get them to run to the board and write up a category in each column that starts with the corresponding letter i.e. A, B, C, or D.
I do it like a relay only allowing one at the board from the team and making them run back to pass it to someone else.
*It's great for teenage learners as they love being active.
Sometimes I do it at the start of the lesson to wake them up, or at the end.