This activity is a review for Algebra I or 7th/8th grade math laws of exponents.
I place the problems all over the room, students are in partners and "travel the world" together. After each problem (in a different city), they are to check their answers with me - it is their "passport," and if they are right, then I stamp their paper and they move on to another city. The kids really enjoy it - it keeps them moving - and engaged at their own pace!