We'd noticed that √ symbol on the calculator. Mr Gregg had mentioned what it meant, and then said, "forget about that; it's not really a Year 4 thing. No really, forget about it."
But the class didn't forget. And not only were they lamentably poor at forgetting, to make matters worse, from time to time they would chant, "Square root! Square root!"
"I'm glad you've probably forgotten what that even means," Mr Gregg would say then.
But the class aren't quite as good at forgetting as they are at some other subjects (more forgetting lessons needed!), so it hasn't gone away.
finding the square numbers. Then we checked on the square roots of them.
√100 = 10
√81 = 9
and so on. A forest of hands went up. A complete failure to forget!
And to round up the lesson, a little algebra.
Maybe, now it's all out in the open, we can all relax and forget a bit more comfortably.