First Grade Common Core Worksheets 1.OA.6 Add and Subtract within 20
The following attachment is one week of math worksheets, including a quiz for Friday. Each day is designed to be copied front and back; the front page is the focus standard of the week and the back page is review of the previously taught concepts. This week has been designed to fit into the third nine weeks of the yearly progression, but could be used any time after you have taught the review concepts. You could also use the front of the sheets in isolation and use the review pages later, after you have covered those objectives.
The focus concept this week is:
Adding and subtracting within 20, with a focus on making ten and creating easier problems with known sums.
CCSS.Math.Content.1.OA.C.6 Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8 + 6 = 8 + 2 + 4 = 10 + 4 = 14); decomposing a number leading to a ten (e.g., 13 – 4 = 13 – 3 – 1 = 10 – 1 = 9); using the relationship between addition and subtraction (e.g., knowing that 8 + 4 = 12, one knows 12 – 8 = 4); and creating equivalent but easier or known sums (e.g., adding 6 + 7 by creating the known equivalent 6 + 6 + 1 = 12 + 1 = 13).
The review concepts this week are:
CCSS.Math.Content.1.OA.A.1 Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.1
CCSS.Math.Content.1.OA.D.7 Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. For example, which of the following equations are true and which are false? 6 = 6, 7 = 8 – 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2.
CCSS.Math.Content.1.MD.A.2 Express the length of an object as a whole number of length units, by laying multiple copies of a shorter object (the length unit) end to end; understand that the length measurement of an object is the number of same-size length units that span it with no gaps or overlaps. Limit to contexts where the object being measured is spanned by a whole number of length units with no gaps or overlaps.
*On these worksheets, students are asked to compare the length of two lines and to determine which one is longer. They are also asked to justify their answers. According to the North Carolina Unpacked Content document, a correct answer could be “Line A is longer than Line B. I used square tiles (paperclips, etc.) and Line A measured 5 tiles and Line B measured 3 tiles.”
Do you need more practice with this objective? I have another week of worksheets that focuses on this standard and it is also in my 1st Nine Weeks Bundled packet.