LESSON PLAN

Equality and Inequality

Apothem Team

Grade 1 · Number

LESSON AT A GLANCE

Warm-up

5 min

Explore

15 min

Consolidate

10 min

Practice

12 min

Exit ticket

3 min

Warm-up

I will show you a number sentence. Thumbs up if true, thumbs down if false. 3+4=7 (true). 5+3=9 (false). 8=8 (true: pause here for discussion). 4+6=3+7 (true: this one generates debate). The last example is the central learning moment.

Explore

Pairs work with relational thinking cards: find the missing number in 6+4=5+? without calculating both sides. Reason about the relationship: if one addend increases by 1, what must happen to the other to keep balance? This is genuine algebraic thinking.

Consolidate

Practice

Students sort 8 number sentences into TRUE and FALSE, recording reasoning. Exit ticket: write your own TRUE number sentence that has + on both sides of the = sign.

Exit ticket

Students sort 8 number sentences into TRUE and FALSE, recording reasoning. Exit ticket: write your own TRUE number sentence that has + on both sides of the = sign.

TIP 4+6=3+7 being TRUE is the most important moment in this unit. Many students will say it is false. Use the pan balance to settle the debate physically. Evidence beats intuition.

WORKED EXAMPLES

A student says 4+6=3+7 is false because there is not just one number after the equals sign. How do you respond?

The equals sign does not mean the answer comes next. It means both sides are the same amount. Does 4+6 equal 10? Does 3+7 equal 10? Are both sides the same amount? Then the sentence is TRUE. Use the balance to confirm physically.

Walk through the relational reasoning for 8+?=9+4.

Right side: 9+4=13. So 8+?=13. What is 13-8? 5. But without calculating both sides: 9 is 1 more than 8, so the ? must be 1 more than 4 = 5. Both methods work; the relational method is more algebraic.

MATERIALS

•Pan balance

•Linking cube towers

•True/False card sets

•Student whiteboards

•Relational thinking task cards

WATCH FOR

!Equals-as-answer is extremely persistent. Counter it in every lesson with true/false sentences that have expressions on both sides. This is the single most important target in this unit.

!Students may think the not-equal symbol means less than because it looks like a crossed-out equals sign. Distinguish it explicitly from the greater-than and less-than symbols.