# Obs - How can I make y3 rounding numbers more interesting?

Discussion in 'Mathematics' started by Jools1808, May 15, 2011.

1. ### Jools1808

Hi,
I'm a student teacher and I'm being observed for a lesson teaching y3 children to round 2 or 3 digit numbers to the nearest 10 or 100. They also need to be able to give estimates for their sums or differences.
I think I'm being a bit silly, but I don't understand what the estimating sums and differences means...it's Sunday, my brain is dead from a weekend of planning and the national strategies have left me panicking. Can someone enlighten me?
I also can't seem to think of a way to make this maths interesting and more 'real'. I love teaching active lessons and the children really enjoy this, but I'm struggling to think of a way to make this happen in rounding. Can anyone suggest anything?
Thanks so much in advance.

2. ### FlippantFlyer

Lets say you have 513 + 197 which rounds to 500 + 200 = 700. Then 700 would be the sum estimate. The difference estimate would be 500 - 200 = 300. I can't advise on senario on 'spicing it up' for year 3 as I'm secondary/FE.

3. ### bombaysapphireStar commenter

I read something on here years ago about telling a story about rounding. You are walking along a road and know the people in the houses that are multiples of 10. It starts to rain when you are outside a house e.g. 83 and you have no coat or umberella. What is the number of the friend's house that you should go into?
It gives a reason that if you are outside 85 you might as well go forward to 90.
Counting on in 10s through transitions (e.g. 790 what comes next ) is useful as that can be a sticking point for the weaker students.

4. ### alabasterNew commenter

Rounding is very handy when shopping, so can be used to know whether you have enough money to buy the collection of items you have put in your basket if you only have a certain amount of cash. I would probably plan along these lines for young kids - although I do teach at secondary.

5. ### Jools1808

Thank you both so much for your help. I thought it might be something as simple as that, but I'd got myself all worried!
I love the idea of the story and am definitely going to have a go at something like that with them.
Really appreciate you taking the time to help me feel so much better about planning this lesson.

6. ### AnonymousNew commenter

Rounding is boring to teach - generally useful in adding up bills from receipts.
They need to know multiples of 10 either side of a number. You'd be surprised how hard some children find that. Also some children don't appreciate 100 or 200 is also a multiple of 10.
Useful for estimating answers (does your answer seem right?) e.g. 24 + 32 is about 20 + 30 = 50 so if you get 100, well you're wrong. 23 x 6 is about 20 x 6.
You can challenge higher pupils e.g. estimate 23 x 42 = 20 * 40 = 800. Give or take.
Have fun