. My DS has a lovely maths teacher this year, who hates seeing kinds bored and disengaged in class, so last week he taught a group of 4 boys on my DS's table Pythogoras' Theorem and gave them a few simple problems to solve. He usually gives them all sorts of maths and logical puzzles to work on to keep them busy after they have done what everyone else is working on.
Why teach them Pythagoras's theorem? I have a lovely task that explores this and leads to this theorem - it will be spoilt for anyone knowing it already. There is sooo much out there without accelerating - the second sentence sounds perfect .... they could do the UKMT junior challenge or the PMC or NRICH or ....
I think the teacher just showed it to them as something interesting while they were working out co-ordinates of triangles on a grid, rather than teach it as such... I'm afraid I don't have any more details of what exactly happened - I was lucky to get anything at all out of my DS in reply to my 'what have you been doing at school today?'... His usual answer is 'nothing much' or ' I don't remember'!
You are right, though, there is no point in speeding up if there are a lot of other interesting things they could do. The task you mentioned sounds very interesting - is it something you could share, please? If it is, I could try to take DS through it in a few weeks's time - maybe he will forget the formula by then!
They did do the junior maths challenge, quite a few of them got through to the second stage. I think we have been very lucky with teachers in Y5 and Y6 - they are all really good and do push those kids who would do with a bit of a challenge. Sometimes, parents may need to have a chat with a teacher if it's a bright child who would happily get away without having to do too much, but once they are aware, they don't let them hide.