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Samantha Fummerton
Mth 492
Final Project Lesson Plan
6/11/12
Lesson Plan Title: Properties of Rational Numbers: Inverse Property of Addition
Subject/ Grade level:
Mathematics/ 7th
State standard:
(7.NS.1) Apply and extend previous understandings of addition and subtraction to
add and subtract rational numbers; represent addition and subtraction on a
horizontal or vertical number line diagram.
a) Describe situations in which opposite quantities combine to make 0.
b) Show that a number and its opposite and a sum of 0. Interpret sums of rational
numbers by describing real-world context.
c) Understand subtraction of rational numbers as adding the additive inverse.
Key Words: Additive inverse, inverse property
Background knowledge:
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This lesson will directly follow a lesson about the Identity of addition. They
should have a clear understanding of what it is.
Should have a previous understanding of addition and subtraction and can
represent using a number line.
Materials:
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Review Worksheet
Additive Inverse Bingo Cards
Extra Credit ticket: tickets to be handed out at the end of a game that are worth 1
extra credit point for homework assignments
Homework assignment
Students should each have their own math notebook
Lesson Goal:
The students will recognize and apply the Inverse Property to simplify
expressions of addition
Lesson Time:
45 minutes (1 class period)
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Outline:
This lesson will directly follow a lesson about the Identity Property. They Identity
Property may have been covered on a Monday and Tuesday and we would start
the Inverse property of addition on Wednesday.
I would start the class by handing out review worksheet #1 (attached) where the
students would review adding and subtracting positive and negative integers on a
number line. They would only have 10 minutes to complete the worksheet, and
then we would go over it as a class.
Next I would write 5 different types of sample problems on the board and ask the
students to copy them into their math notebook. After about ten minutes I would
ask for volunteers to come up and solve the problems. The sample problems
would be as follows:
-3 + _ =0
5 + _=0
2 + -2 = _
20 + _ = 0
100 + -100 = _
I would ask a question to the class: what do all of these problems have in common?
I would hope for a response of that they all equal 0, or the opposites add to equal
0. After this I would introduce the new vocabulary word: Additive Inverse. I
would have them write the vocabulary word in their math notebook with the
definition. I would explain that an additive inverse is the number that you add to
get a sum of 0. I would have them recall that 0 is the identity for addition and that
an additive inverse is used to get the identity element of the operation of addition.
Next I would have them write some math sentences in their notebook. For
example:
-3 is the ______ inverse of ________.
5 is the additive _______ of ________.
After discussing what an additive inverse is I would then ask for volunteers of
who can tell me when we use additive inverses in real life. I would want them to
write these in their math notebook. I would hope to get answers of:
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Having 4 dollars then going to the store and buying 4 dollars worth of
candy. You would be left with 0 dollars.
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Walking 6 blocks to school (positive direction) then walking 6 blocks
home (negative direction) and being back where you started (0).
Now that they have the definition I would introduce the additive inverse bingo
cards. I will explain that the game is a lot like regular bingo, accept if I call out a
number, they get to cover the numbers additive inverse. For example if I call out
B5 the students would have to find a B-5 in order to get the square. Whoever gets
a bingo would get an extra credit ticket. This game would only be played in the
last 10 minutes of the class period.
Before the students leave the class they will each be given a homework sheet that
is to be completed in their math notebook and brought back to class the next day.
Assessment:
The students will be turning in their review worksheets after they complete them.
I will also be keeping track of the students learning with their math notebooks
these will be taken home daily and their homework assignments should be done in
them. I will be able to grade their homework assignments to track their
understanding.