Standard 
Lessons 
Worksheets/Games 
1.OA.A.1, 1.OA.A.2 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. 
Add, Subtract within 20 level 1 

1.OA.B.3 Apply properties of operations as strategies to add and
subtract. Examples: If 8 + 3 = 11 is known, then
3 + 8 = 11 is also known. (Commutative property of
addition.) To add 2 + 6 + 4, the second two numbers can
be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12.
(Associative property of addition.) 

1.OA.B.4 Understand subtraction as an unknownaddend problem. For example, subtract 10  8 by finding the number that makes 10 when added to 8. 

1.OA.C.5 Relate counting to addition and subtraction (e.g., by counting on 2 to add 2). 

1.OA.C.6 Add and subtract within 20, demonstrating fluency for
addition and subtraction within 10. 
Addition
(Use Fingers) 
Addition 
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. 

1.OA.D.8 Determine the unknown whole number in an addition or subtraction equation relating three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 + ? = 11, 5 = _  3, 6 + 6 = _. 
Missing Addend 
Standard 
Lessons 
Worksheets/Games 
1.NBT.A.1 Count to 120, starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral. 

1.NBT.B.2, 1.NBT.B.2a, 1.NBT.B.2b, 1.NBT.B.2c Understand that the two digits of a twodigit number
represent amounts of tens and ones. Understand the
following as special cases: 
Understand 2digit numbers 

1.NBT.B.3 Compare two twodigit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and <. 
Compare twodigit numbers 

1.NBT.C.4 Add within 100, including adding a twodigit number and a onedigit number, and adding a twodigit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding twodigit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten. 
Addition (no regrouping) 

1.NBT.C.5 Given a twodigit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used. 

1.NBT.C.6 Subtract multiples of 10 in the range 1090 from multiples of 10 in the range 1090 (positive or zero differences), using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. 
Standard 
Lessons 
Worksheets/Games 
1.MD.A.1, 1.MD.A.2 Order three objects by length; compare the lengths of two
objects indirectly by using a third object. 

1.MD.B.3 Tell and write time in hours and halfhours using analog and digital clocks. 

1.MD.C.4 Organize, represent, and interpret data with up to three categories; ask and answer questions about the total number of data points, how many in each category, and how many more or less are in one category than in another. 
Standard 
Lessons 
Worksheets/Games 
1.G.A.1 Distinguish between defining attributes (e.g., triangles are closed and threesided) versus nondefining attributes (e.g., color, orientation, overall size); build and draw shapes to possess defining attributes 

1.G.A.2 Compose twodimensional shapes (rectangles, squares, trapezoids, triangles, halfcircles, and quartercircles) or threedimensional shapes (cubes, right rectangular prisms, right circular cones, and right circular cylinders) to create a composite shape, and compose new shapes from the composite shape. 

1.G.A.3 Partition circles and rectangles into two and four equal shares, describe the shares using the words halves, fourths, and quarters, and use the phrases half of, fourth of, and quarter of. Describe the whole as two of, or four of the shares. Understand for these examples that decomposing into more equal shares creates smaller shares. 
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