Parentheses: How big of a change can they make!?

Once students understand the order of operations, they often just get stuck doing increasingly difficult practice problems. That's a sure-fire way to squelch learning, though. Here, students determine where to place parentheses to make the greatest change in an expression.

Objective

Students will add sets of parentheses to expressions to see how large of a change they can create.

Steps

1. First, I model the process and then give them a sample to try: 7 × 3 + 7 × 2
2. I show my best answer (see below) and then present four more samples (available here as a printout)
3. I reveal my best answers, then ask students to think about what patterns or rules they spotted to help them place their parentheses. They write these out as 3 to 5 tips to create a guidebook.

Downloads

• Sample problems
• Sample answers