Thursday, March 19, 2009

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

1. This week's 2nd grade Investigations (TERC) assignment:

Guess My Rule Questions:

NOTE: Students use the given data to figure out additional information

1. A Grade 2 class was playing Guess My Rule. There were 21 students in the class. 8 were wearing stripes. How many students were not wearing stripes? Show your work. Write an equation.

2. A Grade 3 class was playing Guess My Rule. 6 students were wearing glasses. 18 students were not wearing glasses. How many students were in the class? Show your work. Write an equation.

3. A Grade 2 class was playing Guess My Rule. 12 students were wearing sneakers. 10 students were not wearing glasses. How many more students were wearing sneakers? Show your work. Write an equation.

2. From a similar point in the 2nd grade Singapore Math curriculum (Primary Mathematics 2B, p. 114):

Mrs. Coles bought 18 mangoes. Mrs. Lambert bought 28 mangoes. How many more mangoes did Mrs. Lambert buy than Mrs. Coles?

Matthew learns to spell 7 words every week. How many words does he learn to spell in 5 weeks?

The students in a class borrowed 26 books from the class library. There were 34 books left. How many books were there in the library at first?

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3. Extra Credit:

Given that all math problems have students using given data to figure out additional information, discuss why the Investigations problem set, but not the Singapore Math problem set, includes an explanatory note about this for parents.