Thursday, September 18, 2008

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

1. From the beginning of the grade 2 Investigations curriculum (Counting, Coins, and Combinations, Family Letter about Benchmarks/Goals):

7 + 3 = 5 + 1 = 5 + 2 =
6 + 4 = 6 + 1 = 2 + 8 =
5 + 5 = 1 + 9 = 2 + 7 =

2. From the beginning of the grade 2 Singapore Math curriculum (Primary Mathematics 2B, p. 13)

1 more than 76 is
1 less than 76 is
10 more than 72 is
10 less than 76 is

2 more than 76 is
2 more than 76 is
20 more than 76 is
20 less than 76 is

2 more than 38 is
10 more than 63 is
20 more than 80 is
2 less than 75 is
10 less than 86 is
20 less than 94 is

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Extra Credit: 

Which problems does your 7-year-old find most challenging?  Most interesting?

2 comments:

Obi-Wandreas, The Funky Viking said...

The singapore math way also teaches kids what these operations really mean. With my eighth graders I know that I'll have to teach them that "4 less than x" does not mean 4-x.

At least, however, the Investigations problems are, for once, making the kids do real math.

Kathryn said...

The first set of problems is the reason that most kids hate math--because they're boring! When will the people writing these books realize that kids like to be challenged and use their brain a little bit?

And I agree with the other comment here--junior high kids always have trouble with the 4 less than x thing, when I taught middle school, my seventh graders had a lot of trouble with that (because they didn't really have a very strong understanding of it in the first place). It's important, though!