Common Core: Number & Operations in Base Ten
2.NBT.B7
Add and subtract within 1000, 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. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and … Read More “2.NBT.B7”
October 1, 20182.NBT.B8
Mentally add 10 or 100 to a given number 100-900, and mentally subtract 10 or 100 from a given number 100-900.
October 1, 20182.NBT.B9
Explain why addition and subtraction strategies work, using place value and the properties of operations.1
October 1, 20182.NBT.A1
Understand that the three digits of a three-digit number represent amounts of hundreds, tens, and ones; e.g., 706 equals 7 hundreds, 0 tens, and 6 ones. Understand the following as special cases:
October 1, 20181.NBT.C6
Subtract 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.
October 1, 20181.NBT.A1
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.
October 1, 20181.NBT.B2
Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:
October 1, 20181.NBT.B2b
The numbers from 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones.
October 1, 20181.NBT.B2c
The numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to one, two, three, four, five, six, seven, eight, or nine tens (and 0 ones).
October 1, 20181.NBT.B3
Compare two two-digit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and
October 1, 2018