Friday, September 3, 2010

Math problems of the week: 2nd grade Investigations vs. Singapore Math

I. From a 2nd grade Investigations math homework sheet assigned 8/9 of the way into the school year:

II. From a multiplication assignment from the beginning of the second half of the 2nd grade Singapore Math curriculum:

III. Extra Credit

1. Should the child whose answers to the first problem set are recorded above be required to redo the problem with pictures of items repeated in 8 rows, 3 columns; 6 rows, 6 columns; and 7 rows, 4 columns? (Extra credit: how many pictures in total does that amount to?)

2. What about the Singapore Math students? Are they missing out on something by never being required, anywhere in the curriculum, to draw items repeated in rows and columns in order to "represent" multiplication?


Linda said...

I am a math specialist at a school that uses Singapore. No, Singapore doesn't require students to draw models of multiplication, but it does use picture models and arrays for multiplication when it is introduced in first grade. Picture models are considered incomplete models of multiplication (arrays are preferred), so Singapore is correct in limiting the use of the picture model.

It would be silly for a teacher to require the student to redo the pictured assignment even though the child did not follow the exact directions. The objective should have been for the child to demonstrate that he or she understands multiplication, which is exactly what the child did (I would have enthusiastically commented on using two different methods). Unfortunately, we all know far too many teachers who would value the direction-following more than the math knowledge.

Linda said...

Whoops, just one method- but a very nice one.

Deirdre Mundy said...

Our Saxon math book has addition and subtraction problems where the student is supposed to draw the pictures,then write a "number sentence" and then find the answer.

My first-grader inevitably scowls and just writes the answer. Or the "number sentence and answer" in the space for the picture.

Luckily, we homeschool, and I really don't care whether she draws pictures in math class or not! After all it's not like she doesn't get enough drawing in during her free time!

(My husband and I also let her take some of her timed tests orally, with US writing the answers. It's amazing how much faster she can go when she doesn't have to struggle with handwriting!)

GPC said...

I always question the point of drawing pictures and writing sentences in math. I do understand that the idea is to reinforce the concept and I think it can be very helpful when students are being introduced to a new concept.

But it seems unnecessary when children already understand the concept but just need to do a lot of problems to get to the point of automaticity. I can see this getting really tiresome, especially for more advanced students.