1. Addition and Subtraction to 1,000
September 8-9, 2015
September 15-16, 2015

2. Standard CCSS.MATH.CONTENT.3.NBT.A.2
Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.

3. Objective
Students will use place value understanding and properties of operations in order to perform multi-digit arithmetic (addition and subtraction) up to 1000.

4. Homework Due on Friday , September 11th Due on Tuesday, September 15th
Worksheet 1: Adding and Subtracting Up to 1000
Due on Tuesday, September 15th
Worksheet 2: Word Problems

5. Essential Questions How can sums and estimates be estimated?
What strategies can be used to find sums and differences?
How are addition and subtraction alike? Different?

6. Addition of Numbers

7. What I Know
Students are to complete the following example in THEIR journals: =

8. Rules for addition + 12 +124 Line up all your numbers by PLACE VALUE.
Add up all numbers starting at the ones place.
Add tens and hundreds, remember to carry the ‘1’, if necessary:

9. Ways to show addition (Follow teacher on chart paper)
Estimate.
Use Models
Addition Algorithm
396
+142

10. Subtraction of Numbers

11. What I Know
Students are to complete the following example in THEIR journals: =

12. Rules for Subtraction Subtraction (-) means to take away.
The difference is the answer to a subtraction problem.
To subtract, numbers are lined up by the place value of their digits.
Decomposing a number means moving a group of numbers to the next lower place value.
Decomposing is needed when the bottom digit is greater than the top digit in a place-value column1

13. Rules of Subtraction
Read the problem and identify what is being subtracted, if necessary.
Line up the numbers by the place value of their digits, if necessary.
Subtract the digit in each place value. Hint: Start from the ones place.
Decompose a number, if needed.
Hint: Move a group of numbers to the next lower place value.
Interpret the difference. “The difference of _______ and _______ is _______.”

14. Rules for Subtraction Line up your numbers by PLACE VALUE.
Subtract the ones, regroup if necessary.
Subtract the tens and hundreds, borrow from the next number and regroup if necessary.
Perform an ADDITION check.

15. Classwork Math Text Books: 9/8/2015 & 9/9/2015 (Addition)
Pages 100 – 102 # 1-17
(Using Models) Pg 95 # 4-9

16. Classwork 9/15/2015 & 9/16/2015 (Subtraction) Page 161 # 3-11

17. Exit Slip (Complete in Journal)
Aarya read 573 pages during the PG County Summer Reading Challenge. She was only required to read 399 pages. How many extra pages did Aarya read?

18. Reminder
Quiz on Adding and Subtracting up to 1000 on Wednesday, September 16th.