Math Lesson- Reflection

Lesson Title: Manipulative Subtraction

Standards:

K.CA.1 Solve real-world problems that involve addition and subtraction within 10 using modeling with objects or drawings. (E)

K.CA.3 Find the number that makes 10 when added to the given number for any number from 1 to 9 (e.g., by using objects or drawings), and record the answer with a drawing or an equation. (E)

Objectives:

Roll a dice to get a number to subtract from ten, create the inverse of the problem by adding the remaining value to the subtracted amount.

Primary Goal: Add and subtract within values of ten and create problems to record data.

In a lesson, we must prepare to go into it with flexibility. To achieve the lesson outcomes for the assignment, the lesson had to be changed to occur in a large group, rather than the small group, intervention style that I had originally intended. Another modification included the teacher (myself) writing out the math problems as the children explained. Overall, these modifications did not affect the learning outcomes for the students.

I anticipate that the “a-ha” moment of the lesson plan was creating the inverse operation. Using the blocks to display and count out physical values. By writing it out on paper, I was able to show to the symbols and numbers as well as show how to move the numbers around to create the inverse. The children were often much quicker with answering the first subtraction problem than they were with answering, “How do we get back to ten?” These moments showed part-part-whole addition/subtraction and showed the benefits of using a manipulative to model counting, addition, and subtraction. This activity could be completed using ten fingers, counter toys, etc.

As I planned this activity, the idea was to do small group with the children. This would have allowed for more direct and personalized instruction and reduced distractions. However, since I did not plan the activity to be conducted the way it was, I did not have strategies in place to prevent this. I tried to support learning and engagement by using student-based turn taking. Meaning, students would raise their hands if they wanted to roll the dice or share the remaining value.

Some changes I would make to this lesson before repeating it in the future include emphasizing writing/recording data and minimizing materials. I would have the children bring their own papers to the carpet to write and record the math problems for content integration and deeper comprehension. Having me write the problems for the children to see took away from the engagement of the opportunity. Even having them write it with me would have deepened the experience. Because the children all had their own materials in the large group (ten math links cubes and a six-sided dice), the children lost interest in the activity quicker than I would have liked. This activity is quick and easy and would be ideal for intervention or review/practice work for students needing support with adding and subtracting.

The method of assessment for this activity was having the students read the math problem that we had worked together to write out. Students were assessed based on whether or not they could read printed numbers 1-10 and if they used the correct name of mathematical symbols. During the activity I observed the students for understanding to see if they were removing the proper number of cubes from the base set and reminding them to add the remaining blocks from the base to find our values. The assessment showed that students fully grasped the concept and used the proper terminology. To ensure this, I described the numbers and symbols as I wrote them and would call on students with their hands in the air to read the final problem. Modeling these behaviors and giving examples set the tone for this lesson and reflected in student responses.