Identify Related Facts - Day 1 of 2

I write the following word problem on the board/chart paper:  (also available as a PPT Identify Related facts)

Jan has 4 pencils.  Matt gives her 9 more pencils.  How many pencils does Jan have?

I instruct the students to use connecting cubes to model the problem.  I guide the discussion using the following questions throughout the activity:

• What do we need to find? (How many pencils Jan has)
• How can we use cubes to show our addition sentence?  (I can put 4 red cubes and 9 blue cubes)  I would then write the sentence on the board/chart paper.
• What is another related addition sentence that we can write? I would then write that one on the board as well.
• How can we use our cube train to show a related subtraction problem? (I can take off the 9 blue cubes from the cube train.)  Write this subtraction sentence on the board.
• What is another related subtraction sentence?  Write that one as well.

I like to continue through these steps to model a few more fact families.

Guided Practice: (located on the second slide of Identify Related facts)

I like to have some addition and subtraction problems ready and have students identify the related facts. 

Prior to moving onto independent practice, I have shoulder partners share why one of the example facts is not a fact family.

I use the Identify related facts worksheet for independent practice.

In this video, you will see a student using counters to help him to model the math problems:

For struggling students, I make a set of 5 addition and 5 subtraction related fact cards (using index cards) and we play memory to help them identify the related facts.