Common Core 3.NBT.2 ACOS 3.11 and 2003 COS 3.2 Marilyn Whatley Lincoln Elementary

*A fact family is a set of related addition and subtraction number sentences that use the same numbers. You are practicing fact families every time you use XTRAMATH.com Examples of fact families: = 7 7 – 4 = = 7 7 – 3 = = – 8 = = – 2 = 8

I can fluently add and subtract numbers.  Fluently means that I can get the correct answers when I add and subtract and that I can work without wasting my time.  I will make a plan as I solve a problem and use strategies that I know.

 Watch and listen as I model how to use what I know (a strategy) to help me solve a problem.  (next 5 slides)

There are 24 students in Mrs. Davis’ class. There are 23 students in Mrs. Whatley’s class. What is the total number of students in the two classes? This part is the information I will need to solve the problem. I need to read it carefully. It is a good idea to read it twice and make a picture in my head. This part is the question. It tells me what I need to find an answer for.

First, I picture what the information says: CCCCC CCCC CCCCC CCC Mrs. Davis’ Class Mrs. Whatley’s Class

Then I read the question to see what to do with the information.  What is the total number of students in the two classes? I know that total means how many Are there in all, so I am going to have to put them all together, or add.

To find a total, I need to add all of the students together. CCCCC CCCC CCCCC CCC Mrs. Davis’ Class Mrs. Whatley’s Class +

Now, I need to EXPLAIN how I got my answer. I added the 23 students in Mrs. Whatley’s class to the 24 students in Mrs. Davis’ class and got a total of students +24 students 47 total students I can use words, numbers, or both to explain my answer !

Now, let’s work a problem together. Turn to the next page in your Math Journal. Put today’s date at the top. Put pencils down because first, we have to read the information. Then we need to “picture the information”.

There are 16 third graders and 22 fourth graders on the playground. How many total students are on the playground? What is the information? Now picture that in your mind.

Cccccc ccccccc ccc 3 rd graders Cccccccccc ccccccccccc c 4 th graders There are 16 third graders and 22 fourth graders on the playground. How many total students are on the playground?

Cccccc ccccccc ccc 3 rd graders Cccccccccc ccccccccccc c 4 th graders There are 16 third graders and 22 fourth graders on the playground. How many total students are on the playground? What is the question? What should I do?

Cccccc ccccccc ccc 3 rd graders Cccccc cccc 4thgraders How many total students are on the playground? I need to add to find the total. +

22 fourth graders + 16 third graders 8 Work the problem in your journal. Be sure to explain how you got your answer! 3

Examples of answers: I added the third graders to the fourth graders and got a total of 38. I got my total of 38 by adding 22 plus fourth grade students + 16 third grade students 38 total students on the playground

Now, it is YOUR turn to work with a partner to solve a problem. Remember to read the information. Picture it in your mind. Read the question. Make a plan. Both partners work the problem in their math journals. Explain how you got your answer!

There are 15 fourth graders and 23 fifth graders in the gym. How many total fifth graders and fourth graders are in the gym?

Share students’ work using ELMO document camera. More practice for students to try ON THEIR OWN on the next slides.

There are 35 horses and 24 cows in the barn. How many total animals are in the barn?

Sara and her dad went fishing. Sara caught 12 fish and her dad caught 21. How many total fish did dad and Sara catch?

First graders went on a field trip. 53 rode on the first bus and 57 rode on the second bus. How many total first graders rode the two buses?

On Sunday, Mel texted her friends 47 times. On Monday, Mel texted her friends only 32 times because she had homework to do. How many total times did Mel text on these two days?