How important is knowing how to round up/down numbers

[momtothreeboys]

My oldest isn't grasping the concept. I've spent the past 3 days working on rounding numbers up and down and he's just not grasping the concept. I'm wondering if I need to keep working on it until he gets it or if I can move ahead and just give him a few problems daily review while moving ahead. I'm using math mammoth 1B if that helps any.

[mommy4ever]

My dd6 is doing 1B right now as well. We just finished that part.

 

We used an abacus to teach. From 5 up got the next ten, we did it visually with a ribbon dividing between.

 

We also did a number line chart. 0-10, 10-20, 30-40, etc coloring in the 5 and up.

 

She grasped it pretty well.

[momtothreeboys]

My dd6 is doing 1B right now as well. We just finished that part.

 

We used an abacus to teach. From 5 up got the next ten, we did it visually with a ribbon dividing between.

 

We also did a number line chart. 0-10, 10-20, 30-40, etc coloring in the 5 and up.

 

She grasped it pretty well.

Interesting idea and I'm going to try it tomorrow.

[PenKase]

We also use MM and just completed the section on rounding in 1B. With my dd, I made sure to go over the "teaching" section thoroughly, and had her progress at a 1 page a day speed to to make sure the concept cemented in the brain since it was completely new to her. I find that moving at this pace, with brand new topics, really helps in making things stick.

 

Have you tried printing up the extra practice pages that Maria provides or play the games listed at the beginning of the chapter?

 

Maybe using a tangible number line will help. What about reviewing the "teaching" portion daily before working through the problems, or using it for copywork, or posting it where easily visible?

 

HTH

[momtothreeboys]

We also use MM and just completed the section on rounding in 1B. With my dd, I made sure to go over the "teaching" section thoroughly, and had her progress at a 1 page a day speed to to make sure the concept cemented in the brain since it was completely new to her. I find that moving at this pace, with brand new topics, really helps in making things stick.

 

Have you tried printing up the extra practice pages that Maria provides or play the games listed at the beginning of the chapter?

 

Maybe using a tangible number line will help. What about reviewing the "teaching" portion daily before working through the problems, or using it for copywork, or posting it where easily visible?

 

HTH

Yes I did print off the extra practice sheets. I didn't see any games that worked on the rounding up/down concept. It's like he just guesses, he looks at say number 57 and says 68. Or 89 is the number and he says 100. Seriously its totally random his guesses. I think I'll have my husband give him some numbers with me somewhere out of the room. One thing I've learned is sometimes he just goofs off for me at times and if someone else does the work with him he'll show he can get it.

[PenKase]

Ahhhh, I see. When dd guesses, I know right away it's because there's something in the teaching/explaining that she didn't get and led to the inevitable deer in the headlights stare, crickets singing in the background. :001_smile:

 

Using the number line helped dd see where the tens were with relation to the numbers she was supposed to round down or up to. Maybe your ds needs help in "seeing" the tens??? As to the goofing off.....a good old dose of having daddy help always does the trick here! :D

[Daisy]

I didn't worry about it. I taught it in 4th grade right before we head into long division and my daughter understood it right away. It really isn't necessary for anything before that point, imo.

[Corraleno]

I drew a number line and used the analogy of a bridge — one of those rope bridges across a gorge you see in adventure movies. If you're part-way across the bridge and it starts to collapse, which way do you run? If you're at least half-way across (rung 5, 50, 500, etc), you run to the other side. If you're not quite halfway across, it makes more sense to run back the way you came. Once my DS could "see" it that way, he totally got it.

 

Jackie

[Farrar]

When I taught remedial math to middle schoolers, I found that a surprising number of kids didn't know how - which isn't too surprising, I guess. However, I was surprised at what a difficult concept it turned out to be for some. I would have thought it was something 1st and 2nd graders could get, but I saw some 6th graders struggle to get finally get it - smart kids who flew through other math concepts once someone gave them some attention. So I second what Daisy said. Move on and then come back to it in a year or even more. It's not essential yet and it's harder than it looks for some kids.

[SilverMoon]

In second grade? Not necessary. It's going to come around again every year for the next few years. :)

[Penelope]

We use Singapore and did not come across it until 3A Standards. It may be in the earlier Standards levels but we did regular edition before.

 

I think it's sort of a side topic. If they understand numbers well, they should pick rounding up easily later on. It should be pretty easy to understand using money, once they care about money. :D

[*Jessica*]

When Nik doesn't understand a concept I break out the internet links I've collected and find something that can present the idea in a different way, or a game that he can play to practice the concept. So far it has always worked. Here is a rounding game from Jan Brett.

[EKS]

Rounding is actually very difficult conceptually. I'm surprised it's being taught in a first grade book. It is important that he gets it at some point, but it may not happen this time around.

[Laura Corin]

Can you circle back round to this? I often found that difficult concepts became much more simple if they were left for a few months.

 

Laura

[Murmer]

Rounding can be an amazingly useful tool especially when you get to multidigit addition and subtraction...ex. 18 + 56...if you round 18 to 20 (just 2 more) then it is much easier to add = 76 minus the 2 you rounded up 6 - 2 (yeah easy math) 74...no need to carry. Even better for subtraction lets do 56 - 18 round 18 to 20 that mean 36 but you added 2 so now you need to subtract those 2 again easy math 6 - 2 = 4 74 is the answer again no need to carry. Now this does not work for every single situation but it can be a very quick easy way to do math in your head. I believe that is why rounding is in a 1st grade book and it can be a very valuable mental math tool.

As for how to teach it...I love the above abacus idea. Also playing lots of games about making 10 and then use that to help ie 8 + 2 =10 so if it is 8 its close to 10 but a number that ends is 2 is 8 away from 10 because 2 + 8 = 10. It really is about finding and using the easiest 10.