Copied from Ohio Department of Education

CRITICAL AREA #1: Developing understanding of addition, subtraction, and strategies for addition and subtraction within 20
Students develop strategies for adding and subtracting whole numbers based on their prior work with small numbers. They use a variety of models, including discrete objects and length-based models (e.g., cubes connected to form lengths), to model add-to, take-from, put-together, take-apart, and compare situations to develop meaning for the operations of addition and subtraction, and to develop strategies to solve arithmetic problems with these operations. Students understand connections between counting and addition and subtraction (e.g., adding two is the same as counting on two). They use properties of addition to add whole numbers and to create and use increasingly sophisticated strategies based on these properties (e.g., ―making tens‖) to solve addition and subtraction problems within 20. By comparing a variety of solution strategies, children build their understanding of the relationship between addition and subtraction.

The standards below relate to this Critical Area:

 Operations and Algebraic Thinking 1.OA Represent and solve problems involving addition and subtraction. 1.OA.1 1.OA.2 Operations and Algebraic Thinking 1.OA Understand and apply properties of operations and the relationship between addition and subtraction. 1.OA.3 1.OA.4 Operations and Algebraic Thinking 1.OA Add and subtract within 20. 1.OA.5 1.OA.6 Operations and Algebraic Thinking 1.OA Work with addition and subtraction equations. 1.OA.7 1.OA.8 Number and Operations in Base Ten 1.NBT Use place value understanding and properties of operations to add and subtract. 1.NBT.4 1.NBT.5 1.NBT.6

CRITICAL AREA #2: Developing understanding of whole number relationships and place value, including grouping in tens and ones
Students develop, discuss, and use efficient, accurate, and generalizable methods to add within 100 and subtract multiples of 10. They compare whole numbers (at least to 100) to develop understanding of and solve problems involving their relative sizes. They think of whole numbers between 10 and 100 in terms of tens and ones (especially recognizing the numbers 11 to 19 as composed of a ten and some ones). Through activities that build number sense, they understand the order of the counting numbers and their relative magnitudes.

The standards below relate to this Critical Area:

 Number and Operations in Base Ten 1.NBT Extend the counting sequence. 1.NBT.1 Number and Operations in Base Ten 1.NBT Understand place value. 1.NBT.2a, b, c 1.NBT.3

CRITICAL AREA #3: Developing understanding of linear measurement and measuring lengths as iterating length units
Students develop an understanding of the meaning and processes of measurement, including underlying concepts such as iterating (the mental activity of building up the length of an object with equal-sized units) and the transitivity principle for indirect measurement.

The standards below relate to this Critical Area:

 Measurement and Data 1.MD Measure lengths indirectly and by iterating length units. 1.MD.1 1.MD.2 Measurement and Data 1.MD Tell and write time. 1.MD.3 Measurement and Data 1.MD Represent and interpret data. 1.MD.7

CRITICAL AREA #4: Reasoning about attributes of, and composing and decomposing geometric shapes
Students compose and decompose plane or solid figures (e.g., put two triangles together to make a quadrilateral) and build understanding of part-whole relationships as well as the properties of the original and composite shapes. As they combine shapes, they recognize them from different perspectives and orientations, describe their geometric attributes, and determine how they are alike and different, to develop the background for measurement and for initial understandings of properties such as congruence and symmetry.

The standards below relate to this Critical Area:

 Geometry 1.G Reason with shapes and their attributes. 1.G.1 1.G.2 1.G.3