ACE 2.3 The +/- Connection

LARGE GROUP
Today we reviewed counting numbers, natural numbers, whole numbers, integers, and rational numbers during our warm-up. Then we shared homework, discussed algorithms for subtraction from yesterday's problem, and talked about how there is no Commutative Property for subtraction, unlike addition. We had a mini-assessment to see how students are thinking about adding and subtracting positive and negative numbers. Then we worked on Problem 2.3, The "+/-" Connection, on pages 28-29. Students noticed the relationship between addition and subtraction of integers:

Subtracting a positive number is like adding a negative number.
Subtracting a negative number is like adding a positive number.

These two facts can be quite useful in making problems easier to solve. By turning subtraction problems into addition problems, we don't have to come up with complicated algorithms for subtraction. Class notes may be downloaded here for class 7A or class 7B.

LARGE GROUP HW:
ACE 2.3 Homework
Please choose one of the options below to complete.

Option 1
Problems 10-12 and 15 (a, b, e, f, i) & 16 (a, b, e, f, i) on pages 34-35

Option 2
Problems 10-11, 15 (a, b, e, f, i) & 16 (a, b, e, f, i), and 40 on pages 34-39

Do not use a calculator!
Due tomorrow, Thursday, March 18.

SMALL GROUP
Students worked with Cory today. They shared the ACE 2.1 homework, made Subtraction and Absolute Value cards, then worked on Problem 2.3, The "+/-" Connection, on pages 28-29. Please see notes above for Large Group for more about that problem.

SMALL GROUP HW:
ACE 2.2 Homework

Problems 1a-h, 2, 3, and 10-12 on pages 32-34.

Do not use a calculator!
Due tomorrow, Thursday, March 18.