1st Grade Math (Iowa Core)

Operations and Algebraic Thinking (OA)

• 1.OA.A.1 Solve addition and subtraction word problems within 20 with the unknown in any position.
• 1.OA.A.2 Solve word problems that add three whole numbers with a total of 20 or less.
• 1.OA.B.3 Use the commutative and associative properties as strategies for adding.
• 1.OA.B.4 Understand subtraction as finding an unknown addend.
• 1.OA.IA.C.1 Iowa standard: use counting and subitizing to explain addition and subtraction.
• 1.OA.C.5 Link counting on and counting back to adding or subtracting 1 or 2.
• 1.OA.C.6 Add and subtract within 20 using the strategies the standard lists.
• 1.OA.IA.C.2 Iowa standard: add and subtract within 10 fluently.
• 1.OA.D.7 Understand what the equal sign means and decide if equations are true or false.
• 1.OA.D.8 Find the missing whole number that makes an addition or subtraction equation true.

Number and Operations in Base Ten (NBT)

• 1.NBT.A.1 Count forward and backward starting from any number within 0–120.
• 1.NBT.B.2 Know that a two-digit number is made of tens and ones (a–c: a ten, the teens, and multiples of ten).
• 1.NBT.B.3 Compare two two-digit numbers by looking at their tens and ones digits.
• 1.NBT.C.4 Add within 100, including a two-digit number plus a one-digit number or a multiple of ten, using place value.
• 1.NBT.C.5 Find 10 more or 10 less than a two-digit number mentally and explain the reasoning.
• 1.NBT.C.6 Subtract multiples of ten from multiples of ten in the range 10–90.

Measurement and Data (MD)

• 1.MD.A.1 Put three objects in order by length and compare two lengths using a third object.
• 1.MD.A.2 Measure length by laying equal units end to end with no gaps and counting them.
• 1.MD.B.3 Tell and write time to the hour and half hour.
• 1.MD.IA.B.1 Iowa standard: identify pennies and dimes and count mixed collections up to 100 cents.
• 1.MD.C.4 Sort, show and talk about data in as many as three categories.

Geometry (G)

• 1.G.A.1 Tell defining attributes of shapes apart from non-defining ones, and build and draw shapes with given attributes.
• 1.G.A.2 Combine 2D or 3D shapes to make composite shapes and new shapes from them.
• 1.G.A.3 Cut circles and rectangles into 2 or 4 equal parts and call them halves or fourths.