General Information
Benchmark Instructional Guide
Connecting Benchmarks/Horizontal Alignment
Terms from the K-12 Glossary
- Number line
- Natural Number
Vertical Alignment
Previous Benchmarks
Next Benchmarks
Purpose and Instructional Strategies
The purpose of this benchmark is to extend the place value work of plot, order and compare from grade 1 by increasing the number set to 1,000. In grade 1, students ordered numbers in ascending order only.- Instruction includes the use of numbers presented in multiple ways and different forms.
- Instruction includes the understanding that the value of a digit is impacted by its position in a number.
- Instruction includes the use of place value charts, place value cards, place value disks, place value chips and base ten blocks (MTR.2.1).
- Instruction includes the use of number lines using benchmark numbers to support comparing.
- Instruction includes the understanding that numbers can be reordered in both ascending and descending order.
Common Misconceptions or Errors
- Students may incorrectly plot a three-digit numbers in a number line.
- Students may not understand that a representation of a smaller portion of a number line (200 − 220) may have the same physical size as a representation of a larger number line (0 − 1,000).
- Students may have difficulty comparing two numbers that have the same digits in a different order (i.e., 852 and 582).
Strategies to Support Tiered Instruction
- Instruction includes the use of a hundreds chart and base ten blocks. Teacher shares two numbers that have the same digits, but the numbers are in different places.
- For example, using numbers like 852 and 582, the students build the two numbers on place value charts. Teacher has students write the number under each of the base ten blocks representation. With the visual representation of the numbers available, ask which number is greater and which number has fewer of each of the base ten blocks. If students identify the incorrect number, teacher points out that there is a greater number of hundreds/flats in 852 than in 582.
- Instruction includes the use of number lines with benchmark numbers to aid in placement of 3-digit numbers. May use multiple number lines with different end numbers to show the need to focus on the portion where the numbers lie.
- For example, teachers begin with having students label a number line with end benchmarks 0 and 1,000. Then, have students determine what number is located in the middle (500). Students can then further label all of the 100 multiples on the line from 0 to 1,000. Next, show students three numbers (i.e. 435, 442, and 427) Teacher can then show a second number line and discuss that the end numbers can now change to get closer to these three numbers and label the ends with 400 and 450. Work with students to label the multiples of 10s that exist on this line. Then, have students determine where these three numbers are located.
Instructional Tasks
Instructional Task 1 (MTR.2.1)
Provide students with five numerals (i.e., 1, 8, 5, 4 and 0).- Part A. Create four different three-digit numbers that have a 4 in the hundreds place.
- Part B. Arrange the numbers created in order from greatest to least. Explain why which number is the greatest.
- Part C. Using two of the numbers created from Part A, write a statement using > or < to compare.
Instructional Task 2 (MTR.1.1, MTR.2.1, MTR.4.1, MTR.5.1)
Class Plotting on an Open Number Line
Materials: 4 Clothespins, 4 index cards, 4 feet of string or rope,
Teacher: Hang a piece of string in the classroom.
1. Ask a student to think of a three-digit number that has 3 tens in it and a 1 in the hundreds place. Write that number on an index card. Ask another student to place the number anywhere on the piece of string (open number line) using a clothespin.
2. Ask a student to think of a three-digit number that has 1 hundred in it. Write that number on an index card. Ask another student to place the number on the piece of string (open number line) using a clothespin. Ask the class if it should be placed to the right or the left of the first number. Ask “Is this number more or less than our first number?”
3. Ask a student to think of a three-digit number that has 1 hundred in it that would come after the 3 tens number. Write that number on an index card. Ask another student to place the number on the piece of string using a clothespin. Ask the class if it is greater than, less than, or equal to the first number on the number line. Ask the class if adjustments are needed to make room for the new number on the open number line (string). Make adjustments as needed.
4. Ask a student to think of a number that would come between the first and second number. Write that number on an index card. Ask the class “Should this number be placed closer to the first number or second number? How do you know?” Ask the class if adjustments are needed to the number line more accurate now that they have all the numbers placed. Make adjustments as needed.
5. Ask students to independently come up with at least three different true statements from the numbers on the class number line using >, < or = symbols. After giving students time to come up with statements, call on students and write their findings. Ask students to evaluate if they are in fact true statements. Remind students to come up with both greater than and less than statements.
Sample Class Number Line:
Instructional Task 3 (MTR.1.1, MTR.2.1 , MTR.4.1, MTR.5.1)
Teacher provides 6 to 10 numbers on cards in either standard form, expanded form, word form or pictural form. Ask students to place them in ascending order. If any numbers are equal, they can be placed on top of each other to show that they are located at the same spot because they represent the same number. Ask students to come up with at least five different true statements from the numbers using the <,>, or = symbols.
Instructional Items
Instructional Item 1
Use the number line below to plot the numbers 234, 247, 205.Instruction Item 2
Use <, > or = to make the comparison statement 567 __ 576 true.*The strategies, tasks and items included in the B1G-M are examples and should not be considered comprehensive.