Math Student Work
Math Student Work
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Grade 5 Unit 6 /Math A Unit 4~ Expressions with Parentheses
What Does This Look Like In:
K 1 2 3 4 5 A B
Students need concrete examples of when parentheses are used in an expression. All too often, students are simply taught that what is inside the parentheses needs to be computed first. Students have little idea what the numbers in the expression represent.

Students use the Kidspiration Program to illustrate and solve problems about creatures with different attributes. In this example, the student writes an expression to determine the number of eyes each of the groups of creatures has. There are three boggles with three eyes each. Therefore: 3 x 3 = 9 eyes. There are four blurbles with five eyes each. Therefore: 4 x 5 = 20 eyes

The pictures help the students to evaluate each set separately by connecting each of the expressions within a set of parentheses with a picture. In the first example, students are asked to combine the sets. In this example, the creatures are the same, but instead of combining the sets, the sets are being compared. Therefore, students are finding the difference and not the combined total.


It is important that students understand what each of the numbers in the expression represent. The 7 is the number of snipsnaps. The 10 is the number of teeth each crunch has. Questioning students to explain what the numbers represents is important. Students might also evaluate each of the expressions within a set of parentheses. The 63, then, is the number of teeth of all of the snipsnaps, and 90 represents the number of crunch teeth.

Obviously, the examples above are fun. Students should also see examples that are more practical. Geometry is a good place to start.

Click the link above for Math B to see other practical examples of evaluating expressions.


Indicators:
1.5.2.2 use grouping symbols to apply the associative property and evaluate expressions.
1.6.3.2 evaluate simple algebraic expressions and simple formulas

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