# 6th Grade Common Core Math

## Tips, Math Practices, and Ideas about Operations with Decimals

on September 5, 2013

## Topic 3- Operations with Decimals

September 6-19 (Sep. 20 Posttest Topic 3/Pretest Topic 4)

#### Lesson

3-1 Estimating Sums and Differences

6.NS.3

#### AZ AIMS Standards

M06-S1C3-02

3-2 Adding and Subtracting 6.NS.3 M06-S1C2-07
3-3 Estimating Products and Quotients 6.NS.3 M06-S1C2-03, M06-S1C3-02
3-4 Multiplying Decimals 6.NS.3 M06-S1C2-02, M06-S5C1-01
3-5 Dividing Whole Numbers 6.NS.2 M06-S1C2-03
3-6 Dividing by a Whole Number 6.NS.3 M06-S1C2-03
3-7 Dividing Decimals 6.NS.3 M06-S1C2-03, M06-S1C3-02, M06-S5C1-01
3-8 Evaluating Expressions 6.EE.2.c M06-S1C2-07, M06-S3C3-04
3-9 Solutions for Equations and Inequalities 6.EE.5 M06-S1C2-07, M06-S3C3-01
3-10 Problem Solving: Multiple-StepProblems 6.NS.3 M06-S5C2-01, M06-S5C2-02

## Technology Integration Weekly Highlight

Mr. Avery’s 6th graders write a post and create a movie about decimals.

## Tip of the Week

The use of estimation strategies supports student understanding of operating on decimals.

Example:

First, students estimate the sum and then find the exact sum of 14.4 and 8.75. An estimate of the sum might be 14 + 9 or 23. Students may also state if their estimate is low or high. They would expect their answer to be greater than 23. They can use their estimates to self-correct.

Answers of 10.19 or 101.9 indicate that students are not considering the concept of place value when adding (adding tenths to tenths or hundredths to hundredths) whereas answers like 22.125 or 22.79 indicate that students are having difficulty understanding how the fourtenths and seventy-five hundredths fit together to make one whole and 25 hundredths.

Students use the understanding they developed in 5th grade related to the patterns involved when multiplying and dividing by powers of ten to develop fluency with operations with multi-digit decimals.

## Double Dose Recommendations

Continue 5th grade cyclical review based on IE;   Kim Sutton Math Routines (Number Line Workbook, Place Value, Math Drills to Thrill).

## Math Practices

Make “Why?”; “How do you know?”; and “Can you explain?” classroom mantras.

If the answer is correct, ask those questions — “Why?” “How do you know?” “Can you explain?”

If the answer is wrong, you can address it the same way you would if it was right, and they often figure out where they went wrong. Don’t tell them, “No” or “Wrong”, allow them a chance to talk through it.

Why does asking “Why?” support the mathematical practices of

reason abstractly and quantitatively (MP.2) and

construct viable arguments and critique the reasoning of others (MP.3)?