Lesson: Equal Means Interchangeable
scale (2 sides that can equal out)
5 or more groups of small objects – balls, paperclips, marbles, erasers, staplers, markers, blocks, etc.
4 scale signs (attached)
8-12A 1.0 Students identify and use the arithmetic properties of subsets of integers and rational, irrational, and real numbers, including closure properties for the four basic arithmetic operations where applicable:
A1.1 Students use properties of numbers to demonstrate whether assertions are true or false.
(Set up stations ahead of time, with sides labeled and objects on either side that can be compared)
Launch: Present 3 problems that review recently acquired skills, provide 3-5 minutes for solving, solicit answers, guide student-led clarification if needed
Write on the board: What do we mean when we say that something is equal to something else?
On an empty space on the board, write 5-10 = signs, with space on either side. Circulate and hand markers to students and ask them to fill in the “equation”. You might get answers like “6 = 6”, “0 = Nothing”, or “Math = Hard”. Let them be creative. After you have enough examples, ask students to give a definition to the word “equals”.
Divide students into 3 or more heterogeneous groups. Allow 5-8 minutes at each station. Circulate and guide. Students should sketch what they put on each side to achieve equality. See attached station labels.
Discuss some solutions with entire class.
Students complete attached worksheet independently or in pairs.
7 - 2 + 3 [ ] 4 -1 +3