As a TTOC (Teacher Teaching on Call) I like games and activities that are interactive, can be adapted to any subject and age, and do not require a lot of prep or materials.
Some of my favourites include Tic-Tac-Toe and Basketball Trivia.
This is a new one I haven't tried yet, but can't wait to give a go.... it does require a bit of prep, but could easily be done in a short amount of time.
1. Make a simple chart with enough boxes so that each student in the class has one. Give this chart to students (you could even ask them to make a chart and number it 1-30 [or however many people are in the class] This is where students will write answers to problems.
2. Assign each desk a number (to match the chart) If desks are in a circle it will make movement easiest, but regardless of desk seating plan, be sure to give clear instructions on which direction students move during "SCOOT" (You may wish to put # signs on the desks to make it clearer)
3. On each desk put a flashcard face down with a problem on it (Math, Socials Studies, Vocabulary, etc) You may put the # on the back to make it clearer for students which question/answer they are working on.
4. Students flip over the flashcard and solve the problem, writing the answer on their chart sheet. When you yell "SCOOT" they flip the card back over and move to next question/problem/desk
5. Once everyone has gone to each desk and gotten a chance to answer each question, you can end the game and review the answers they wrote on their charts.
*You an decide how much time to wait between calling "SCOOT"
**Review rules, safety in moving from desk to desk before starting the game.
Here is an example created for a class of 12 students reviewing percents: