Using the Quick Flash routine, show students the first set of 5 & 6 dot cards, which you can find in the resource section. Ask students to determine the total number of dots. Repeat this with the second set of 5 & 6 dot cards and then compare the arrangements.
Advanced Preparation: Write the following story on a piece of chart paper to use throughout the rest of the lesson.
Cheyenne and Hannah went to the Sweet Spot. Cheyenne bought 7 cookies and Hannah bought 6 cookies. How many cookies did they buy?
Start the lesson by explaining to the kids that they will be solving a story problem on their own and at the end of class we will discuss the problem at the end of math. I will read the problem to the students to help them remember to visualize the problem and also have a few students retell the story in their own words. I want the students to be able to not only identify what is going on but be able to explain it back to me. It is important that they learn to understand the problem before they try and solve it. I also ask if there will be more or less than 7 cookies. I remind the students that they can use pictures, cubes, numbers, and/or equations to show their thinking.
I then give each student a copy of the problem (see resource entitled The Sweet Spot) and have them get to work.
Note: As students finish, they can go right into Center Time choices.
Students will choose form these activities once they finish their story problem. These are all repeated activities and the students will know how to do each of them. As you circulate around the room, note the different strategies that students are using to combine numbers. You will want each of the strategies represented during the session wrap up. You will most likely see students counting all, counting on, known fact, and using something known (4+4=8 so 4+3=7).
Center Choices ( FYI: I have included the description used when I introduced each activity). The students can choose any math center. Remember, the focus is combining sums and all of these activities focus on that skill.
1. Dice Sums: I start by gathering the students in front of the focal point (in this case I am using the Smart Board). I explain that we are going to play a game called Dice Sums. I show them the tools that they will need (dice, pencil and recording sheet). I then roll the 2 dice and explain that we will need to figure out how many dots there are in all. I remind them that when we are adding, it is called finding the sum. After the sum is determined, the answer should be recorded on the answer sheet. The game is a race not with your partner but rather with all of the numbers between 2-12. We want to see which number is first to be rolled 8 times. I will continue to play this with the group until the group understands how to play. The students are starting at any number less than 120and can read and write numerals and represent a number of objects with a written numeral. The students are explaining the problem and identifying an entry point to the problem(CCSS.Math.Content.1.NBT.A.1).
2. Connect 5: I roll the two dice and ask "what numbers I rolled?" Once they are identified, I ask how many dots there are? I then add the idea of getting the sum of the two numbers. I take a minute to explain this term. Once I am given an answer, I ask "how do you know?" Once you agree on the sum, ask a child to find the sum on the board and mark it with an x (marker for demonstration, the students will use chips during their game play). Play a few more rounds until you feel everyone has the idea.
3. Combine and Compare Me: I start by explaining to the kids that we are going to learn a new game called Combine and Compare Me with Dots. It is played the same way as me, except that you are combining two cards and finding the total number of dots. Once you have the total, you compare it to your partners total and then say "Me" if you have the greater amount of dots. If the totals are the same, the players each turn over one more card to determine the winner of the round. Keep playing until all of the cards have been flipped. The students are constructing viable arguments of their approach and using their knowledge to critique the approaches of others CCSS.Math.Practice.MP3. The students are making use of structure by decomposing numbers to combine them (i.e. 7+5 is seen as 5+5+2) CCSS.Math.Practice.MP7.
I will call the students to gather in front of the Smart Board. I will be using the document camera to project students work as their strategies are shared. The focus for this discussion is that students model a variety of ways that the found the total of the two quantities and that standard notation is modeled.
I will call students to share based on the strategies that were used. I want to make sure that I have a variety of approaches modeled. As each strategy is shared, I will draw it on the chart paper that was prepared at the beginning of the lesson. I will also label each one with a letter. When we are done sharing, I will ask the students to pick which strategy was similar to their own. They can then share this information out. The students using addition within 20 to solve word problems. They are using objects, drawings, and equations with a symbol for the unknown number to represent the problem. CCSS.Math.Content.1.OA.A.1).
Students continue to practice the writing the numerals 1-8. These have been introduced in previous lessons. Make sure to note reversals and take time (during another part of the day) to clarify with students.