# what is the meaning of adding and subtracting.

Mar 5, 2016 1:37pm

it tell my student how to add and subtract.

• Math
• 2
• Common Core

4

• Mar 5, 2016 1:39pm

1. join (something) to something else so as to increase the size, number, or

2.take away (a number or amount) from another to calculate the difference.

• Mar 7, 2016 12:34pm

This sounds like a simple enough question but there's a lot of students that begin to confuse the two by middle school. I found some success with the use of chips and tiles. In grade school, adding means to combine while to subtract means to take away. There's a connection between the two. If they can see that subtraction means the addition of the opposite of the subtractor, then they would be able to tell the difference. This is not easy feat but the time that they put in to discover this pattern would be so worth it.

• Mar 13, 2016 12:11pm

Hi Niya! For these questions I really love this learning progression because it gives a nice flow of how those operations build:

• Apr 2, 2016 7:30pm

OK, but I have found that kids are more successful with both addition and subtraction if they learn from the get-go that numbers can be partitioned into a total and two parts (number bonds). When you know two of the three numbers, you can find the missing number either by addition or by subtraction. That way, children are not locked into a single understanding when they get to word problems where they could EITHER add OR subtract to solve the problem.

We have been practicing number bonds within 10 and then within 20 since the start of school and it is really paying off now.

This week my first graders were solving measurement problems like the following.

"Kim's pencil is 12 cm long. Bob's pencil is 8 cm long. How much longer is Bob's pencil than Kim's?"

One student solved it using addition, 12 = 8 + ?cm
Another student solved it using subtraction, 12 – 8 = ?cm

We use EngageNY which does a great job of building this foundation in Grades K, 1, and 2.