Friday, July 26, 2013

Math problems of the week: 4th grade Everyday Math vs. Singapore Math

Two ways to lead 4th graders to the formula for the volume of cuboids.

I. Everyday Math (Student Math Journal Volume 2, pp. 316-317) [click to enlarge]:

II. Singapore Math (Primary Mathematics 4B Workbook, p. 151) [click to enlarge]:

III. Extra Credit
Does it help the Everyday Math "discovery process" that "the tallest stack" in Box 6 is shorter than the box's height?

1 comment:

Barry Garelick said...

I don't think the stack in Box 6 is shorter than the actual height. It's just that the stack is in the middle of the box and so it isn't apparent that the top cube of the stack hits the top of the box. In the other pictures, the stacks used to measure height are towards the edges so it's easier to see that the top cube reaches the top of the box. Nevertheless, it doesn't help to have such ambiguity in a diagram.