This is a great math activity for the first week of school (or for when you are working on the order of operations). Students create mathematical expressions that represent things about them. For example, they could write "2 x 4 + 3" for how old they are.
I usually have them do it for homework during the first week. When they come into school the next day, their partner has to solve their expressions to learn more about them. My students usually get a kick out of trying to make them as challenging as possible.
You can really use this activity for any math number sense topic. For example, if you're working on decimal operations, you could ask students to include decimals in their expressions.
My students love this activity and it's a great way to get to know each other! Hope you enjoy it too!