Primary Standards:
MAFS.2.NBT.1.1 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:
a 100 can be thought of as a bundle of ten tens – called a “hundred.”
b The numbers 100, 200, 300, etc. refer to one, two, or three hundreds (and 0 tens and 0 ones).
MAFS.2.NBT.1.3 Read and write numbers to 1000 using base-ten numerals, number names, and expanded form.
MAFS.2.NBT.1.4 Compare two three digit-numbers based on meanings of the hundreds, tens, and ones digits, using >, =, and < symbols to record the results of comparisons.
Connecting Standards:
MAFS.2.NBT.2.8 Mentally add 10 or 100 to a given number 100-900, and mentally subtract 10 or 100 from a given number 100-900.
Content Knowledge:
Throughout the elementary years, students develop an understanding of our base-ten number system, it takes 10 ones (a bundle) to make a ten, 10 tens (another bundle) make a hundred, and 10 hundreds (yet another bundle) make a thousand. This pattern continues throughout our number system, and the ways in which we write numbers, add and subtract numbers, and compare numbers are all based on place value concepts. Understanding place value is foundational to understanding how numbers work.
In this Unit, students extend understanding of 2-digit numbers to 3-digit numbers (and 1,000). Students should still experience the use of physical materials to represent bundles and groups of ones, tens, and hundreds. Explorations at this level focus on building a deeper understanding of place value. As students build numbers with base-ten materials, talk about the value of each digit, and read and write numbers they focus on the meaning of place value and make connections to both the standard and expanded forms of written numbers. When writing 3-digit numbers in expanded form, students decompose the number into its place value components. 235 becomes 200 + 30 + 5. Rather than simply saying there is a 3 in the tens place, students should show that the 3 is a 30 (or 3 bundles of tens) reinforcing place value understanding. These understandings will also support students as they represent and compare 3-digit numbers, e.g. 345 > 435 because the 4 in 435 represents 400, which is more hundreds than the 3 in 345.
GCG 1 Learning Goal: Identify the value of 3-digit numbers and equivalent representations
- Step 1: Use concrete and pictorial models to represent hundreds
- Step 2: Use concrete and pictorial models to represent 3-digit numbers
- Step 3: Decompose 3-digit numbers in different equivalent representations
GCG 2 Learning Goal: Read and write numbers to 1,000 in standard, expanded, and word forms
- Step 1: Identify the actual value of each digit in a three-digit number
- Step 2: Read and write numbers to 1,000 in standard and expanded form
- Step 3: Read and write numbers to 1,000 in standard, expanded and word form
GCG 3 Learning Goal: Count by 1, 5, 10 and 100 to 1,000
- Step 1: Count forward and backward by ones from any three-digit number
- Step 2: Skip count by 5 from any given multiple of 5
- Step 3: Skip count by 10 and 100 from any given number
GCG 4 Learning Goal: Use place value to compare three-digit numbers using >, =, and < symbols