This is great for an end of topic review and requires no preparation. Put students into groups of about 4 and give each group a blank sheet of paper.
Get them to write the letters A to Z on the sheet. Their task is to think of a keyword from the topic starting with each letter of the alphabet. Give them some sort of time limit on this dependent on their ability and concentration span. As they’re working you can call out how many words each group has every now and then to give a bit of an atmosphere of competition.
When the time limit’s up you can move to the next stage. Get one member of each group to come up to the front and give them each a piece of scrap paper. Ask the first student what keyword they have beginning with the letter A. If they give a suitable keyword they stay in, if not they lose a life (put a cross on their scrap of paper) and they have to swap with someone else in their team. Obviously any cheating by other team members calling out results in the loss of a life.
Then ask the next student what they have for B, then the next for C, etc. When you’ve been through each of the students at the front once or twice you can then make things harder – after they name a keyword they have to answer a question about that keyword correctly to stay in. If they get it wrong they lose a life and swap with someone else on their team, as before.
The game continues until all there’s only one team left, or when you get to Z, in which case the team with the most lives remaining wins.
These rules are by no means set in stone – I seem to change them every time I play this, trying to strike the right balance between competition and teams going out early (and hence losing interest), as well as ensuring everyone in the class is involved.