SWBAT use relationships among different combinations of 10. SWBAT fluently produce complements of 10.

Students are engaged in a choice of activities that develop conceptual knowledge and fluency of complements of 10.

5 minutes

Advanced Preparation: Create a two row survey with a question at the top and the rows labeled yes or no (see picture in lesson resource).

As students enter the classroom for math, I instruct them to read the question and then answer it with a tally mark. Once everyone has answered I will start the conversation.

"Let's count the results for each category. How many people said "yes?" How many people said "no." Now I would like you to give me one way we could represent our results using an equation. What are some I Notice statements that you could make? Who could write an expression using the < or > sign?" The Core expects 1st graders to be able to represent a number of objects with a written numeral (CCSS.Math.Content.1.NBT.A.1) and also compare different quantities using symbols (CCSS.Math.Content.1.NBT.B.3).

"The students are reasoning abstractly and quantitatively. It is expected that mathematically proficient students make sense of quantities and their relationships in problem situations (CCSS.Math.Practice.MP2)." In this case, the students are distinguish the two categories as separate entities that also are parts of the whole.

*The picture in the section resource exhibits the results of the above questions.*

I continue to throw in surveys throughout the year. This allows me to spend less time in the isolated context of a unit and more time applying the concepts to real life situations. The CCSS expect that first graders can "organize, represent, and interpret data with up to three categories; ask and answer questions about the total number of data points, how many in each category, and how many more or less are in one category than in another (CCSS.Math.Content.1.MD.C.4)."

15 minutes

I have the students gather as a group and face the Smart Board in my room. On the whiteboard, I have a blank ten frame. I use a magnetic one but you could always just draw one in.

**I have used these ten frame cards throughout the year. If this is the 1st time you are using them, you will want to make sure that the students understand the the structure of a frame. This being that there are 5 boxes on top and 5 boxes on the bottom.*

*"We are going to have a ten party today! The rest of math class will focus entirely on making ten.I am really excited and I hope you are too!"*

**"I am going to flash a tens frame card the Smart Board. I will only flash it for about two seconds. I want you to figure out how many dots are on the card. Once you know, I want you to fill your ten frame card with some of the round counters that I gave you. I will then flash the card one more time and you can check your work. I will then leave the image up and ask you to tell the group how you figured out the total number of dots"**

There are two videos int he resource section that allow you to view this discussion in action.

I am asking the students to communicate their thinking to their peers and allowing the students to hear and see a variety of approaches that people are using to solve a task. The CCSS expect students to "communicate precisely to others. They try to use clear definitions in discussion with others and in their own reasoning." (CCSS.Math.Practice.MP6) I am also trying to allow as many students as possible to be called on to articulate their thinking by saying how many dots they saw and how they saw it. Although I ask kids to put their thumb on their chin (once they have an answer), I call on any child. This is something that my students have come to expect. You will have to figure out a system that works for you and your students.

Through this activity, students are also working on developing fact fluency within 10 and the ability to add and subtract within 20 (CCSS.Math.Content.1.OA.C.6).

I repeat this procedure several times or as time allows.

25 minutes

Advanced Preparation: Before class started, I went ahead and set up the stations. Since the students will be able to choose which activity that they want to do, i want to minimize congestion and confusion of where to find the materials for each game. Watch the video to see what I am talking about.

I start station time by walking the students through each of the activities. Although all of these activities have been introduced in previous lessons, we are coming off a 12 day vacation and want to make sure that they are focused, understand the games, and that they truly focus on recording how they made 1o in each activity. They will need their recording sheets for the end of lesson wrap up (next section).

"I want to quickly review each of your station time choices. I am going to ask that you join me on a quick tour as we visit each station. With your help, I will quickly model each activity."

*10's Go Fish:* Advanced Preparation: You will need a set of number cards or playing cards for each team. To play the game you will only use the 1-9 cards. The rest should be discarded for this activity.

*Remember your goal here is to make 10. You start by dealing out 5 cards to each player and then put the remaining cards face down on the table. On your turn, you should look to see if you have any cards (using only 2 cards) in your hand that can make ten. If you do, you pair them up and put them down on the table. You then can pick two new cards up from the pile that is face down on the table. If you can't make 10, on your turn, you can ask the other person if they have a card that you would need. For example, if I had a 3, what card would I want to ask for?*

*Each time I get a new card, I check to see if I can make 10 with that card and a card that's already in my hand. If I can, I out the pair down. If I can't, then my turn is over. If I run out of cards, I can pick two new cards from the deck."*

*"When you have run out of cards, the game is over. You then use the recording sheet (see section resource) to record each combination you collected to make ten. Let's play a sample round, as a class, to make sure everyone understands how to play."*

In this activity, I am asking students to make sense of quantities and their relationships in a problem situation (**CCSS.Math.Practice.MP2**). The students are developing an understanding that if I have a 4, i will always need a 6 to make 10.

*What's Under the Sheet*: Advanced Preparation: You will need a piece of construction paper for each team, connecting cubes, and a recording sheet for each team member. The recording sheet can be found in the section resource.

"Remember, in this game, you use strategies to find out how many cubes are hidden under the sheet. You will be doing the work of master mathematicians and solving for what mathematicians call the unknown."

I then introduce the game to them and model it by playing with another student.

**"You will start by grabbing 10 cubes. You will choose one person to go first and they will be the person that hides the cubes first. Once you have filled out the total number of cubes you are starting with (on your recording sheet), you will then hide some cubes under the sheet (construction paper) and leave some showing on top of the sheet. Let's say that you start with ten cubes. You put 6 under the sheet and four on top. Your partner will then fill out how many cubes are not hidden, leave the hidden space blank and then write the equation**

**___ + 4=10 or 10=____+4. Then that person tries to figure out how many cubes are under the sheet and describes how they figured it out. Then he/she fills in the missing part on the recording sheet."**

In this activity, students are determining the unknown whole number in an addition equation (CCSS.Math.Content.1.OA.D.8). This is a complicated skill and must be worked on throughout the year in order for students to develop a sound understanding and mastery by the end of the year.

*Making Ten With Number Cards*: I use ten frame cards for this. You can use playing cards (minus the 10's, J-K's).

"*The goal of the game is to make as many combinations of 10 as you can. To play the game you will need a deck of ten frame cards (or paling cards). You will take out the tens and just use the 1-9 cards and you will play with a partner (I did make one team of 3 because I had an odd number). To start, you make 4 rows of 5 cards with the numbers facing up. You put the extra cards on the side, face down. The first person scans the cards to find two numbers that make ten, and then picks them up as they say the two numbers. Your partner needs to agree that the cards do make ten. You can check by counting the dots. If you need to do this, I want you to count on from the highest number. After you take two cards, you replace them with two new ones from the "extra" pile that you made at the start.*

*Once you can no longer make any more combinations, you will use the recording sheet (see section resource) to write an equation for each combination. Let's play a few rounds together to make sure everyone understands."*

The students are recording their equations on a recording sheet and using standard notation in doing so. They are modeling their answer with mathematics, which allows them to engage in MP4 (CCSS.Math.Practice.MP4), which states that "mathematically proficient students can apply the mathematics they know to solve problems arising in everyday life, society, and the workplace. In early grades, this might be as simple as writing an addition equation to describe a situation."

It is expected that "1st grade students can add and subtract within 20, demonstrating fluency for addition and subtraction within 10" (CCSS.Math.Content.1.OA.C.6). This activity's repetitiveness allows for this fluency to build.

15 minutes

I gather all of the students back to the carpet area. I ask them to bring their recording sheets from their station time activities and to sit and face the easel. The focus of this conversation is for them to generate all of the two addend combinations of ten.

*"I hope you enjoyed our 10 Party! We have done a lot of work on combinations of ten using two addends. I now want to make a list of all the ways to make ten with two addends. Who can give me one way to make ten?"*

I then start recording their answers on the easel. I set up the chart so that I can easily write the "flip facts/turn around facts" next to each other. There is a picture in the section resource that shows the chart we created.

5 minutes

I finish the lesson with a quick activity that focuses on the fluency of producing complements of ten. There is a video int he section resource that shows the students doing this activity.

"We have been spending so much time on our complements of ten because I want you to be fluent or be able to say them very quickly. We are now going to se show quick you are. I will say a number and I want you to tell me the complement that would make ten. You can shout it out and be as quick as possible."

I find that this makes the idea of being quick fun and is a way to get them to think about producing complements fluently.