Understand that the three digits of a three-digit number represent amounts of… | 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: | 2.NBT.1 |
100 can be thought of as a bundle of ten tens—called a "hundred." | 100 can be thought of as a bundle of ten tens—called a "hundred." | 2.NBT.1.a |
The numbers 100, 200, 300, 400, 500, 600, 700, 800, 900 refer to one, two… | The numbers 100, 200, 300, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds. | 2.NBT.1.b |
Show flexibility in composing and decomposing hundreds, tens and ones | Show flexibility in composing and decomposing hundreds, tens and ones (e.g. 207 can be composed from 2 hundreds 7 ones OR 20 tens 7 ones OR 207 ones OR 1 hundred 10 tens 7 ones OR 1 hundred 9 tens 17 ones, etc.) | 2.NBT.1.c |
Count within 1000; skip-count by 2s, 5s, 10s | Count within 1000; skip-count by 2s, 5s, 10s, and 100s; explain and generalize the patterns. | 2.NBT.2 |
Read and write numbers within 1000 using base-ten numerals, number names… | Read and write numbers within 1000 using base-ten numerals, number names, expanded form, and unit form. | 2.NBT.3 |
Compare two three-digit numbers based on meanings of the hundreds, tens | Compare two three-digit numbers based on meanings of the hundreds, tens, and ones digits, using >, <, =, and ≠ relational symbols to record the results of comparisons. | 2.NBT.4 |
Fluently (efficiently, accurately | Fluently (efficiently, accurately, and flexibly) add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction (e.g. composing/decomposing by like base-10 units, using friendly or benchmark numbers, using related equations, compensation, number line, etc.). | 2.NBT.5 |
Add up to four two-digit numbers using strategies based on place value and… | Add up to four two-digit numbers using strategies based on place value and properties of operations. | 2.NBT.6 |
Add and subtract within 1000, using concrete models or drawings and strategies… | 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, like base-ten units such as hundreds and hundreds, tens and tens, ones and ones are used; and sometimes it is necessary to compose or decompose tens or hundreds. | 2.NBT.7 |
Mentally add 10 or 100 to a given number 100 – 900 | Mentally add 10 or 100 to a given number 100 – 900, and mentally subtract 10 or 100 from a given number 100 – 900. | 2.NBT.8 |
Explain why addition and subtraction strategies work using place value and the… | Explain why addition and subtraction strategies work using place value and the properties of operations. The explanations given may be supported by drawings or objects. | 2.NBT.9 |