WWYD: Bar Models

[Chelli]

I just got done grading my dd8's test on using bar models (Singapore method).

 

On the problems where she actually had to fill in the bar models, not a word problem, just long bar equals 50, short bar equals 38, missing piece to make short bar equal long bar is a question mark.

 

She missed all of these...every single one. She did the wrong operation every time.

 

On the two-step word problems, though, she got all of them correct. She did not draw bar models, though. Just solved the problems correctly by reading them and figuring out the operations that needed to be used.

 

Of course, I'm going to go over the diagram problems she missed. But my question is this: She obviously understands what to do without using bar models based on getting all of the word problems correct. Is it that important for her to be able to fill in the diagrams correctly? Are the bar model pictures that important (or bar models in general) to Singapore?

 

I'm trying to decide if we need to camp on this topic for a couple of days or if she can move on.

[sleeplessnights]

My oldest has the same problem. With word problems he can figure out what to do, do the correct operations, and then get the right answer. If I make him use a bar model, he's lost.

 

I figure that the point is to be able to use the bar model to get the correct answer. The problems might be easy at this stage, but they're only going to get harder. I don't require him to use the bar models, however when we work the problems together I always use the bar models and talk him through it. He's getting to the point now that if I draw the bars, he can get the answer, though he can't draw them himself yet.

 

I'm hoping that by near-constant exposure he'll be able to incorporate them into his problem-solving toolbox.

[Element]

IMHO: Bar models are very important, but I don't think you necessarily need to "camp out" on the subject. She will see bar models over and over and over again as she goes through the program. My ds struggled with bar models when they were first introduced to him last fall (here's a lovely example of an early bar model from ds) but he eventually got the hang of them. Do you use the CWP? It provides many helpful examples of bar models. Another idea is to have her work on graph paper.

[Chelli]

Thanks for the input!

 

We'll just move on to the next chapter, and when bar models come up, I will work through solving them that way with her.

 

She just "gets" math, so I think having to draw out what she's doing doesn't make a lot of sense to her. "I can do it without having to draw anything, Mom!"

 

We do add in the CWP and IP, but haven't covered bar models in either of those yet.

[SorrelZG]

Thanks for the input!

 

We'll just move on to the next chapter, and when bar models come up, I will work through solving them that way with her.

 

She just "gets" math, so I think having to draw out what she's doing doesn't make a lot of sense to her. "I can do it without having to draw anything, Mom!"

 

We do add in the CWP and IP, but haven't covered bar models in either of those yet.

 

I wonder if it would be helpful for you to present the idea of drawing it as pretending to explain the problem to someone who didn't know.

[Mandamom]

I used SM and my ds could do the work up until 4b without the bar models. Once he hit 5a we hit a wall and I had to go back and teach him how to do the bar models. I wish I had done it right the first time. It probably would have helped if we had used CWP also but we didn't. Oh well.