We did nothing but work quadratic formula problems on Friday. I let the students self-organize. Some chose to work alone. Others worked in groups. I gave each group a different problem.

It was a smashing success. The students were mostly engaged and focused non-stop for fifty minutes. The room was noisy. But the talk was (mostly) of math — music to a teacher’s ears. When they had problems, they’d call me over. (“Mister, should we get decimals?” “Yes, on this problem you’ll get fractions.”) I’d show them my answers and let them compare their work to mine, asking them to see if they could find their mistakes.

“Ohhhh,* that’s* what I did wrong!” I would hear behind me as I walked over to help another group.

When they finished one problem, they’d move on to another. (There were plenty to choose from.)

After class, a student came up to me.

“That was easier than I expected!” the student said.

*Group work is magic.*