Unit 3

Place Value, Counting, and Comparison of Numbers to 1,000

 

Grade 2

Math

Unit Length and Description:

 

20 days

 

All arithmetic algorithms are manipulations of place value units: ones, tens, hundreds, etc. In Unit 3, students extend and apply their understanding of place value to read and write numbers to 1000 using base-ten numerals, number names, and expanded form. Students will compare numbers to 1000 by using <, >, and = to record the results of comparisons.

 

Standards:

 

Major Cluster: NBT – Number and Operation in Base Ten

Understand place value.

2.NBT.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, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds (and 0 tens and 0 ones).

2.NBT.2

Count within 1000; skip-count by 5s1, 10s and 100s.

2.NBT.3

Read and write numbers to 1000 using base-ten numerals, number names, and expanded form.

2.NBT.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.

Standards for Mathematical Practice: Should be evident in every lesson.

 MP.2

Reason abstractly and quantitatively. 

MP.3

Construct viable arguments and critique the reasoning of others. 

MP.6

Attend to precision. 

MP.7 

Look for and make use of structure.

MP.8 

Look for and express regularity in repeated reasoning.

Instructional Outcomes

 

2.NBT.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, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds (and 0 tens and 0 ones).

  • I can explain the value of each digit in a 3-digit number.
  • I can identify a bundle of 10 tens as a “hundred”.
  • I can represent a three digit number with hundreds, tens , and ones. (using base ten blocks, place value charts and drawings).
  • I can represent 200, 300, 400, 500, 600, 700, 800, 900 with one, two, three, four, five, six, seven, eight or nine hundreds and 0 tens and 0 ones.

 

2.NBT.2: Count within 1000; skip-count by 5s1, 10s and 100s.

  • I can count within 1000 from any given number.
  • I can skip-count by 5s from any given number.
  • I can skip-count by 10s from any given number.

 

2.NBT.3: Read and write numbers to 1000 using base-ten numerals, number names, and expanded form.

  • I can recognize expanded form.
  • I can recognize that the digits in each place represent amounts of thousands, hundreds, tens or ones.
  • I can read numbers to 1000 using base ten numerals.
  • I can read numbers to 1000 using number names.
  • I can read numbers to 1000 using expanded form.
  • I can write numbers to 1000 using base ten numerals.
  • I can write numbers to 1000 using number names.
  • I can write numbers to 1000 using expanded form.

 

2.NBT.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.

  • I can name the value of each digit represented in the three-digit number.
  • I can compare two three-digit numbers based on place value of each digit.
  • I can use >, =, < symbols to record the results of comparisons.

 

Enduring Understandings:

 

·        Place value is based on groups of ten.

·        Place value allows us to use 10 digits to express numbers up to and beyond 1000

·        The value of a digit depends upon its place in a number.

·        Numbers can be represented in many ways, such as with base ten blocks, words, pictures, number lines, and expanded form.

 

Essential Questions:

 

·        How does the position of a digit in a number affect its value?

·        How can numbers be expressed, ordered and compared?

·        What is the difference between place and value?

·        How does place value help us solve problems?

·        How does the value of a digit change when its position in a number changes?

·        What does “0” represent in a number?