Grade 1 - Strategies for Addition and Subtraction Unit
The Strategies for 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?
- Given an equation, can you create an addition or subtraction situation to match it? How can you prove it matches the equation?
Math Concepts and Skills:
The student solves problems by developing and using strategies for addition and subtraction.
The student:
- finds the sum of a multiple of 10 and a one-digit number (up to 99) in problem situations.
- develops, applies and explains strategies used to add and subtract within 20, such as making 10 and decomposing a number leading to a 10.
- creates problem situations when given a number sentence involving addition or subtraction of numbers within 20; solves the problems created.
- represents word problems involving addition and subtraction of numbers up to 20.
- applies properties of operations to add and subtract two or three numbers—if 4 + 3 = 7 is known, then 3 + 4 = 7 is also known.
Summative Assessment Task
Given a total of 14 lemons, students determine if Mary has enough lemons to make two glasses of lemonade. (0-14)
Students determine if Riley read 17 pages in her book. (0-17)
Instructional Tasks/Formative Assessments
Students determine how many coins Dominic puts in his bank.
Students determine how many cat treats are left in the bag after Colin gives some to his cat. (0-12)
Students determine how many bean plants are left in Hank's garden. (0-19)
Given the number of paintbrushes the art teacher found in a can and on a shelf, students determine if there are enough paintbrushes for the class.
Given three sets of numbers, students determine the total number of birds that come to a birdbath. (0-20)
Students determine how many carrot stick are left on a plate after some are eaten. (0-14)
Students count the total number of mother and baby birds Hailey sees in three trees. (0-18)
Students determine if Tyrone has a total of 20 inches of pencils. (0-20)
Students determine how many pages Jamal read in his book about dogs.
Students determine how many more shoes Evan needs to find in his bedroom to have a total of six pairs of shoes. (0-12)