## Reflection: Student Ownership Introducing the Addition Algorithm - Section 1: Warm Up

There is great value in helping second graders learn to explain their thinking. I always encourage students to talk about how they solved a problem, what they were thinking, and what strategies they used to solve the problem. At first it was a struggle. Students would say, "I just did it," but they were so unaware of the how or why.

Today, a parent came in to tell me how her child, who has been struggling with math, sat down and explained to her how you can take an addition problem that is written vertically and add the tens and then add the ones and put them together. The child said that you can check your work by finding the smiley face number that each number is close to and add them to see if the two answers were close. This child had internalize the process and was then able to really explain the process she was using, one that was based on place value reasoning.

It is a crucial skill that is worth taking the time to stress in each lesson that you teach. If a child knows what he/she is doing, to the point that they can explain it, they can apply that to future math experiences.

Unit 17: Getting Better at Addition and Subtraction
Lesson 8 of 12

## Big Idea: Students are able to add and subtract when numbers are presented horizontally. They add and subtract tens and ones with appropriate fluency. Today they will be introduced to adding two 2-digit numbers presented vertically.

Print Lesson
1 teacher likes this lesson
Standards:
Subject(s):
45 minutes

### Beth McKenna

##### Similar Lessons

###### Cover Up
1st Grade Math » Counting by Groups
Big Idea: Yesterday we added it up and today we cover it up. Students will work in pairs as they cover random numbers on a number grid and ask their partner to figure out which numbers are Covered Up!
Favorites(5)
Resources(17)
Waitsfield, VT
Environment: Suburban

###### Domino Addition: Understanding the Part/Part/Whole Relationship
Big Idea: The big idea of this lesson is the understanding that addition can be represented as parts of a whole and that we can use addition sentences to represent those parts.
Favorites(19)
Resources(20)
Pepperell, MA
Environment: Rural

###### It's As Basic As That
3rd Grade Math » Understanding Multiplication
Big Idea: Students need to master the basic operations. The common core suggests that all four operations are mastered by the end of third grade. This lesson will help determine where to start and what to do next.
Favorites(13)
Resources(11)
Troy, MI
Environment: Suburban