Estimation

[PotteryLottery]

How do you practice estimation?

Y1 DD is trying bit I can tell she is secretly counting

DD's teacher described it as a "sensible guess" which I thought was useful.

Maybe draw some lines and get her to guess how long they are? Maybe draw a set length one as well so she has a clue where to start.

Dt1 used to hate doing this. He'd say why would he want to guess and get it wrong when he could just work it out and get it right.
I used to try and get him to estimate by rounding up or down ie to the nearest 5. But I think he still used to 'cheat' and work it out.

Not an expert by any means, but instead of 'how many are there? Estimate don't count' you could try asking 'are there more or less than x? Estimate!'

That way Redcoats DT1 would still be able to get it 'right' without knowing how many there are exactly.

You would require a fast answer, then you can always go and count to make sure you got it right.

Hi Pottery:

Both DDs find estimation tricky. Certainly DD2 agrees with Meita's DT1 - why estimate if you can work out the answer.

With DD2 I've tried to get her to appreciate that the example is an easy problem - but that the idea of estimation is useful in situations where you're not totally sure you've got the correct answer or don't quite have all the information.....

So in 'real life' I know that movie tickets are about £5 each - so if all 4 of us go I'll need at least £20 (I'm estimating how much to bring/ spend).

I do this a lot in real life with things on sale for £4.99/ £19.99 etc... rounding up £4.99 to £5 and £19.99 to £20 - to estimate it will cost me about £25 in total.

when you have figures - so say estimate the answer 5 x 8 - there will always be the kid that says 40 (DD2 would be one) - but what they're looking for is for you to work with 'easier numbers' - so 8 is pretty close to 10 - and 5 x 10 = 50. Therefore you can estimate that the answer if 50 and know that since you rounded 8 up to 10 the answer will be a bit less than 50.

HTH