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
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
and apply properties of operations and the relationship between
addition and subtraction.
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
and subtract within 20, demonstrating fluency for addition and
subtraction within 10. Use strategies such as counting on; making
(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 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.
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 = ?.
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,
operations, and/or the relationship between addition and subtraction;
relate the strategy to a written method and explain the reasoning
Understand that in adding two-digit numbers, one adds tens and tens,
and ones; and sometimes it is necessary to compose a ten.
multiples of 10 in the range 10-90 from multiples of 10 in the range
10-90 (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.
and Data (1.MD)
lengths indirectly and by iterating length units.
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.
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.
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.
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.
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.