About 3 years ago, I ran across this post from Kate Nowak called Speed Dating. I have used it or a version many times. Students do love it and often laugh about going home and telling their parents they speed dated in math class today!
She suggested placing desks so students are facing one another like this:
I used 2 colors of markers (one purple, one blue). Each card contained one problem involving arithmetic, simplyfing complex number expressions, conjugates, graphing in complex plane and finding the modulus. I used the other color marker to create a parallel set of problems. Each student in one row received a problem from the blue set and the other row from purples. This enabled every student to experience at least one of each type probelm.
Students solved their problem, I confirmed or asked questions to clarify their work. They became the expert of that problem. Every person they “dated” would solve their problem. As Kate’s post mentioned, you can easily assign problems to specific students to differentiate levels if needed.
Pairs would exchange cards, working the given problem. The expert would check the other’s work, confirming or asking questions to help them correct any mistakes. They would get their problem card back. Front row rotates to next person. Repeat. By the end of the round, each student has practiced a variety of problems with immediate feedback as needed.
Exit slips revealed mistakes due to not paying attention to a given operation; a few need reminders of i^2 becoming -1 as one more step to simplify further; several still not comfortable with using conjugate to simplify rational expression of complex numbers. Students enjoy working with others, an opportunity to be out of their seats. Its a chance for them to ask questions of their peers in a smaller setting as opposed to whole-class.
Here is another idea…the Placemat Activity @cheesemonkeysf incorporated to practice arithmetic with complex numbers. Its amazing how quickly one forgets great little spins to use in the classroom. Thank goodness for the open sharing of MTBoS to remind me!