Grade 2 - Addition and Subtraction Unit
Standards covered:
- 2.4 Number and operations
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2.4A
Recall basic facts to add and subtract within 20 with automaticity.
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2.4B
Add up to four two-digit numbers and subtract two-digit numbers using mental strategies and algorithms based on knowledge of place value and properties of operations.
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2.4C
Solve one-step and multi-step word problems involving addition and subtraction within 1,000 using a variety of strategies based on place value, including algorithms.
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2.4D
Generate and solve problem situations for a given mathematical number sentence involving addition and subtraction of whole numbers within 1,000.
The Addition and Subtraction Unit involves understanding the processes of addition and subtraction in order to solve problems and answer questions such as:
- If we know all of the parts, how can we find the whole?
- If we know the whole and one of the parts, how can we find the missing part?
- How can you use place value to explain the strategies you used to solve this addition (subtraction) problem?
- Given an equation, can you create an addition or subtraction situation to match it? How can you prove your situation matches the equation?
Summative Assessment Task
Students determine how many puzzle pieces are left to finish a puzzle.
Instructional Tasks/Formative Assessments
Given a number of boxes put in a truck, students determine how many more boxes need to be put in the truck.
Students determine the number of miles driven by Uncle Ted, when the total number of miles driven is known.
Students find different combinations of coins that add up to 75 cents.
Students determine how many feathers were in a collection to start with, after 42 feathers have been added.
Given the number of students in a primary school, students determine the number of students in grade two.
Students determine if there are enough apples for all the students in grade 2, after several dozen more apples are brought to the school.
Students determine how many stuffed dogs are in a stuffed animal collection.
The N/A classification refers to TEKS Standards that cannot be assessed through problem solving.
For this reason, tasks have not been included for these particular standards.
K.7A K.7B K.9B K.9C K.9D