Bar+Modeling

Seven Steps for Model Drawing -

1. Read problem. 2. Determine the important who and what in the problem. 3. Draw unit bar or bars.

7. Answer the question in a complete sentence, and make sure your answer makes sense.

 * //New!!!//** An organizer for students to help with bar modeling. //Thanks, Nancy!// [[file:bar modeling organizer.doc]]

Practice Problems and Key!

Part-Whole Model for Addition and Subtraction

128 boys and 151 girls took part in a reading contest. How many children took part in the contest?



We know the 2 parts. To find the whole, we add 128 + 151.

Here's a link to [|Thinking Blocks] which gives a nice demonstration of the part-whole addition or subtraction model. Select a picture which shows one bar to learn more about the part-whole model.

Comparison Model for Addition and Subtraction

151 girls took part in a reading contest. 23 fewer boys than girls took part. How many boys took part in the contest?



We are comparing the girls to the boys. We know the bigger quantity. To find the smaller quantity, subtract 151-23.

Here's a link to [|Thinking Blocks] which gives a nice demonstration of the comparison addition or subtraction model. Be sure to select a picture with two bars to hear about the comparison model.