Mathematics Lesson Plan
Rounding
I.
Purpose:
The purpose of this lesson is to familiarize students with concept of rounding numbers to the
nearest ten, hundred, and thousand through an interactive demonstration and using the visual
of a number line.
SOL: Number and Number Sense
3.1 The student will
a) read and write six-digit numerals and identify the place value and value of each
digit;
b) round whole numbers, 9,999 or less, to the nearest ten, hundred, and thousand
II.
III.
Objectives:
 The students will be able to demonstrate whether a given number will round up or
down while playing an UP-down activity with 80% accuracy.
 The students will be able to accurately round the numbers they create with a spinner
by tens, hundreds, and thousands with 80% accuracy when given a spinner and
recording sheet.
Procedure:
a) Introduction
1. Introduce rounding. Ask:
-What is rounding? (a means of estimation used to help with calculations)
-What do you know about rounding?
-When might you use rounding? (when doing mental math, estimating costs in a
grocery store, etc.)
Give wait time and call on students for responses. Tell the students that today we will
talk, move, and learn all about rounding numbers. Initiate the students’ prior knowledge
on place value by talking about tens, hundreds, and thousands place values. Explain to
students that it is important and helpful to understand place value when talking about
rounding numbers.
2. Draw a number line mountain on the board. Pick a 2 digit number and write it on the
board. Have students copy the number line and number on their desks using a dry erase
marker. Ask students to find the tens place of the 2 digit number and underline it. Ask
students to mark the number one digit to the right (“number code”). That is the number
that will determine whether to round up or down (“1-4 stay on the floor, 5-9 climb the
vine”). Use the number line to show students that it takes fewer jumps to move down
when the number is under 4, and less jumps on the number line to move up if the number
is 5 or above. That determines the direction that you round. Practice rounding several 2
and 3 digit numbers. (visual/auditory)
b) Development
Now that the students are familiar with rounding numbers to tens and hundreds,
have the students stand up behind their desks and push in their chairs to play an “UPdown” movement activity. Say:
“We are going to do some mathersizing! Let’s begin by reviewing our rounding
phrase: ‘1-4 stay on the floor (bend down to get your body low to the ground), 5-9
climbs the vine (stand tall and reach upward as if you were climbing a tall vine).’”
1. Use the spinner (numbers 0-9) and paper clip to create a 2 digit number and write
that number on the board. Call on a student to read the number aloud to the class and
have the students write that number on the number line on their desks. Ask the
students to round the number to the tens place. Students will use their bodies to
demonstrate the direction the number will round by either bending down to the
ground or reaching high in the sky, depending on which way they think the number
should be rounded (“1-4 stay on the floor, 5-9 climb the vine”). Call on different
students and ask them what the rounded number should be and write that number on
the board. (visual/kinesthetic/auditory)
2. Repeat this exercise several times, and then increase to 3 digit and 4 digit numbers.
Continue this exercise until you have demonstrated at least 3 examples for numbers
rounding to each the tens, hundreds, and thousands. (visual/kinesthetic/auditory)
3. Have the students get back in their seats and pass out the “Rounding It” handout
and a spinner with paper clip for each cluster of desks. Allow the students to work as
a group or individually to create their own numbers using the spinner and Rounding It
Recording Sheet as their guide. The students should complete the handout to be
turned in for an assessment. (visual/kinesthetic)
c) Summary
Once the students have completed the handout, call on a few students to share
some of their numbers and the ways they rounded each number. Write those
numbers on the board for everyone in the class to see. Collect the handouts.
Ask the students:
“How do you know whether to round a number up or down?”(1-4 goes down, 5-9
rounds up)
“If I want to round to the tens, which number should I look at? To hundreds? To
thousands? (look one place to the right of the digit you want to round)
Collect the handouts as part of the evaluation.
**Differentiation:
For Strugglers: Allow these students to focus mainly on rounding 2 digit numbers
to the tens place using the handout until they have a better understanding of the
material. They may also work with partners to help them better understand the
material.
For Advanced: These students may move forward and make up additional 2, 3, or
4 digit numbers for rounding to the tens, hundreds, or thousands place. These
students may also work with other students who are struggling to help them better
understand the material.
IV.
V.
Materials:
 Magnet with car cut out (for number line)
 Chalk/chalk board
 Dry erase markers (1 per student)
 Rounding It Recording Sheet (1 per student)
 Spinner (1-2 per group)
 Paper clips (1 per spinner)
 Pencils
Evaluation Part A:
 I will know that the students have met the objectives if they are able to demonstrate
whether a given number will round up or down while playing the UP-down activity
when asked to round numbers to tens, hundreds, or thousands.
 I will know that the students have met the objectives if they are able to accurately
complete the Rounding It Recording Sheet with at least 80% accuracy.