# Assessing Ability to Find Combinations of 10

## Objective

SWBAT find 2-addend combinations of 10 (at least five combinations). SWBAT add 2 or more single digit numbers. SWBAT create 2-addend combinations for 20 (at least three combinations).

#### Big Idea

What's Your Number? No, we are not talking about your Sleep Number but rather how many combinations of ten your students can each find as they solve an assessment task.

## Warm Up

5 minutes

I start this part of the lesson by asking the kids to sit in front of the classroom number line.

"Today we are going to change up our Start At/Stop At routine.  We are going to use the numbers between 70 & 100."  Instead of pulling numbers out of an envelope, I am going to ask you to give me a number between  70 & 100.  Who can give me a number between 60 & 100?  Who could give me another number between 70 & 100?. I will put a green dot on the first number given and a red dot on the 2nd number."

You should put a green dot on one stick it note and a red dot on the other.  These will be used to focus on where to start and stop.  You can also practice counting back by placing the green dot on the larger of the two numbers given.  I will call ons students to come up and pint as the class counts.

I will ask a student to point to each number as we count as a whole group.  I will continue this process as time allows.   In this case students are counting up to and back from 100, starting at any number (CCSS.Math.Content.1.NBT.A.1).  This routine is the process in which I can assure that the students are continuously working toward this standard .

## Assessment Activity

15 minutes

Advanced Preparation:  You will need to make copies of the assessment sheet that is in the section resource.

"Today, I want to see how you have grown with your ability to find the combinations of a number. You will solve another Apples and Bananas problem.  I want to see how you have grown as a mathematician and the strategies that you use to find different possible combinations."

I will then read the problem to the class.

"I want you to find as many combinations as you can.  I do expect that you will all be able to find at least 5 combinations.  Remember you can use blocks/cubes if you need them."

As students are working, you will want to circulate and see how students are approaching this task. This task will allow you to see who well they are doing with combination problems, how familiar they are with their combinations of 10, and if they are fluent with combinations of 10.  Fluency with 10, is an expectation for each 1st grader by the end of the year (CCSS.MATH.CONTENT.1.OA.C.6). However, I am expecting the majority of my class to be there at this time (March).

While circulating you can also see if students are working systematically.  Are they using a strategy (flip facts, in order, etc.) to systematically solve the problem through the identification of a structure or repeated reasoning (CCSS.MATH.PRACTICE.MP7)? If not, you can encourage students to do so.

I have included two examples of structures that students could use to find all of the combinations.  I have also included a video of a students explaining how they used the structure they identified to solve the problem.

## Station Time

35 minutes

As students finish the assessment activity, they should play the game Twenty/Twenty.  This game was introduced in a previous lesson.  I have once again included a video, of how to play the game, in the section resource.

This activity has student adding within 20 and demonstrating fluency for addition within 10. They are using strategies such as counting on; making ten; and creating equivalent but easier or known sums (CCSS.MATH.CONTENT.1.OA.C.6).

## Mad Minute

5 minutes

I will ask the students to meet me on the carpet and hand out their sheet for today's Mad Minute exercise.  This routine was introduced in a previous lesson.  Please check out the link to get a full overview of this routine.

I want to really focus on fact fluency and build upon the students ability to solve within ten fluently (CCSS.MATH.CONTENT.1.OA.C.6).  I am going to use the Mad Minute Routine.  This is a very "old school" routine.  However, I truly feel students need practice in performing task for fluency in a timed fashion.  Students need to obtain fact fluency in order to have success with multiplicative reasoning.  Students who don't gain this addition fact fluency by the end of 2nd grade tend to struggle with the multiplicative reasoning in third.  Having this fluency also allows them to work on more complex tasks because the have the fact recall to focus on the higher level concepts.

## Continued Practice

10 minutes

As students finish their Mad Minute sheet, I have them hand it to me and I give them a copy of the True False Sheet that is in the section resource.  Tomorrow's lesson will focus on this concept and look more at missing addend equations and the concept of equality.  I want them to fill this out so that I can quickly see how each child is doing with this idea.  We have worked on True or False equations throughout the year, so the task should be familiar to most of the students.

It is expected that student can look at an equation and decide if the equation os true or not (CCSS.MATH.CONTENT.1.OA.D.7).  This activity sheet allows me to do a quick check in on how secure each student is with this skill.