Equal or Not?
Lesson 6 of 8
Objective: SWBAT determine if two number sentences are equal.
Setting Up the Learning
This standard addresses students' understanding of the equal sign, a concept that is super important for students' later understanding of algebra. A common misconception in equality is that students assume if it "looks wrong", then it can't be true. So 5 = 2+3 is false because 5 is on the "wrong" side.
As students practice equality, they are also getting great practice with math fluency. Fluency is explicitly stated as part of the standards (1.OA.C6), and this lesson is a great example of how to embed number facts throughout the year.
Yesterday (See the We're Tied! lesson) we played a game where we had to figure out: Are we tied? And we talked about how tied means equal.
This is important because you will use the = sign in 2nd grade, 3rd grade and all the way to college!
Today, our goal is to think about: How can we figure out if number sentence are equal?
First, I am going to explain the game. After that, we will practice the game all together.
- Both partners pull a basketball card.
- Partners record their number sentences.
- Each partner figures out how many points he/she got.
- Partners decide: Did we tie? Are the number sentences equal?
I’ll actually play this game with another student, having that student work out their side on the chart paper while I do mine. Throughout this lesson, we are requiring work for each number sentence as evidence of student thinking. This is aligned with CCSS MP2, “Reason abstractly and quantitatively” , which focuses largely on pushing students to coherently represent a problem.
Step 1: Both partners pull a card.
My card says 3+4. ____’s card says 8 - 1.
Step 2: Partners record their number sentences
Step 3: Each partner figures out how many points he/she got.
I’ll reinforce the importance of proving your answer and both the student and I will draw our strategy.
Step 4: Partners decide: Did we tie? Are the number sentences equal?
- I counted on for my card. I said 3, 4, 5, 6, 7. So 3+4 is the same as 7.(Highlight child’s strategy)-Is 3 + 4 the same as 8 – 1?
- I’ll model writing the number sentence and thinking out loud, “3 + 4 is the same as 8-1, so I can write 3+4=8-1”
I’ll model another round with a different student, this time making sure they are not equal.
Student Work Time:
I’ll present 2 cards to students and have them figure out if they are tied on their own. While students work, I’ll make sure they are proving their thinking. The CCSS emphasizes student independence, this is a time I want the students doing all the heavy lifting!
I had students show their thinking on white boards. Attached you'll see how 2 different students showed their thinking. One student used counting strategies for both. Another drew a base ten model for both equations. This is a great example of having students represent their thinking in writing/pictures. The CCSS MP2, "Reason abstractly and quantitatively". This standard is focused on students being able to show what they are thinking using symbols and pictures.
- Are they tied or not?
- What strategy did you use to PROVE that they are tied? This emphasizes the "Construct viable arguments" portion of MP3. Students have to use math to prove their argument.
- What symbol do we need to show that they each got the same number of points?
If time, we will do one more statement together, such as 4 = 6+2. This number sentence forces students to pay attention to the symbols. If they subtract instead of add they will think it is equal.
Game Time! Partner Work
Students play the game with a partner. To differentiate this activity, I just changed the materials students use. See below for intervention ideas!
Gets card set A. Card set A has all totals under 10. Students get ten frames to record how many they got. This helps support students in deciding if they are equal. Because we have worked so much with the ten frame, they can quickly look at both ten frames and see if each one has the same amount.
See attached Basketball game cards and Recording Sheets!
See attached video of 2 students playing the game. You'll see that they both show their strategies for the equations they pulled.
Closing and Exit Ticket
I'll bring students back together and we will do a set of number cards together and determine if they are equal. This will be brief to allow for time for the exit ticket.
Students complete the exit ticket. See attached exit ticket, 2 per page!