# 1st Grade Common Core Resources

These tasks are grade-level formative performance assessment tasks aligned to the Common Core State Standards for Mathematics. Some have accompanying scoring rubrics and discussion of student work samples. Others, such as the Dana Center Early Mathematics Tasks, connect to children’s literature.

The tasks below are arranged by grade level. To search for tasks by mathematical strand or to see information about alignment to specific standards, use the "shortcuts" field at the top of the page, or visit the Common Core mathematical content standards page.

Quick reference: What are these tools?

## Operation and Algebraic Thinking (OA)

• 1.OA.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.

Problems of the Month
• 1.OA.2

Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.

Problems of the Month
• 1.OA.3

Apply properties of operations as strategies to add and subtract.

Problems of the Month
• 1.OA.4

Understand subtraction as an unknown-addend problem. For example, subtract 10 – 8 by finding the number that makes 10 when added to 8.

Problems of the Month
• 1.OA.5

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

Problems of the Month
• 1.OA.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).

Problems of the Month
Formative Re-Engaging Sessions
• 1.OA.7

Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false.

Problems of the Month
Formative Re-Engaging Lessons

## Number and Operations in Base Ten (NBT)

• 1.NBT.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.

Problems of the Month
• 1.NBT.2

Understand that the two digits of a two-digit number represent amounts of tens and ones.

Problems of the Month
Formative Re-Engagine Lessons
• 1.NBT.3

Compare two two-digit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and <.

Problems of the Month
• 1.NBT.4

Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit 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 two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.

Problems of the Month
Formative Re-Engaging Lessons

## Measurement and Data

• 1.MD.1

Order three objects by length; compare the lengths of two objects indirectly by using a third object.

Problems of the Month
• 1.MD.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.

Problems of the Month
• 1.MD.3

Tell and write time in hours and half-hours using analog and digital clocks.

Problems of the Month
• 1.MD.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.

Problems of the Month

## Geometry

• 1.G.1

Distinguish between defining attributes (e.g., triangles are closed and three-sided) versus non-defining attributes (e.g., color, orientation, overall size); build and draw shapes to possess defining attributes.

Problems of the Month
• 1.G.2

Compose two-dimensional shapes (rectangles, squares, trapezoids, triangles, half-circles, and quarter-circles) or three-dimensional 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.

Problems of the Month
• 1.G.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.

Problems of the Month