I laminate these 18 cards for students to use at a math work station. It provides great practice on finding elapsed time. There are 12 cards giving a starting time and an ending time in which students have to find out how much time has passed. There are also 6 cards with either a start time or an end time and the length of the activity. For these cards students have to find the missing start or end time.
I provide students with the answer key so that they can ckeck themselves.