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Overview

This lesson is a hands-on, game-based lesson. It should be part of a larger unit of study on number sense, estimation, and/or place value. The lesson involves students in a game-based activity which gives them a concrete understanding of the relationship between number values, place value, and the accepted mathematical rule for rounding numbers.

This is a College- and Career-Ready Standards showcase lesson plan.

UP:MA19.3.8

Vocabulary

• Unknown quantity
• Mental computation
• Estimation
• Variable
• Reasonableness
• Rounding
• Expression
• Equation

Knowledge

Students know:
• Characteristics of addition, subtraction, multiplication, and division.
• Strategies for addition, subtraction, multiplication, and division.
• Strategies for mental computation and estimating sums, differences, products, and quotients.

Skills

Students are able to:
• Use a variety of strategies to solve two-step word problems involving all four operations.
• Write an equation to represent the problem context, and use a symbol for the unknown quantity.
• Justify strategy and solutions using mathematical vocabulary.
• Determine and justify reasonableness of solutions using mental computation strategies and estimation strategies.

Understanding

Students understand that:
• Mathematical problems can be solved using a variety of strategies, models, and representations.
• Contextual situations represented by multiplication and division.
• Reasonableness of solutions can be evaluated by using estimation strategies.

UP:MA19.3.10

Vocabulary

• Place value
• Round
• Nearest 10
• Nearest 100
• Benchmark number
• Midpoint

Knowledge

Students know:
• Values of the digits in the ones, tens, and hundreds places.
• How to determine what is halfway between two multiples of 10 or 100.
• Strategies for rounding to the nearest 10 or 100.
• Use place value vocabulary and logical reasoning to justify solutions when rounding.

Skills

Students are able to:
• Round whole numbers to the nearest 10 or 100.
• Identify a possible value for a number which will result in a given number rounded to the nearest 10 or 100.
Example: What value will result in 270 when rounded to the nearest 10? Identify the possible values.

Understanding

Students understand that:
• rounding is determining which ten or hundred a number is closer to.

UP:MA19.3.11

Vocabulary

• Fluently
• Sum
• Difference
• Place value
• Strategy

Knowledge

Students know:
• The relationship between addition and subtraction operations.
• How conceptual models support and give understanding to procedures for addition and subtraction.

Skills

Students are able to:
• Use a variety of strategies to solve addition and subtraction problems within 1000.

Understanding

Students understand that:
• Strategies for addition and subtraction will vary depending on the problem.
• Strategies can include place value, properties of operations, and the relationship between addition and subtraction.

Primary Learning Objectives

Students will be able to:

• Round 2- and 3–digit numbers to the nearest power of 10.
• Add ten 2- and 3-digit numbers to determine the greatest sum.
• Understand the value and the place values of a number determines to which power of 10 it should be rounded.
• Identify situations in which rounding estimation can be used.
• Determine when rounding estimation is acceptable or when an exact amount is needed.
• Understand what a nice number is. (A nice number is a number that is a multiple of 10.)

Student Essential Question: How do I decide what ‘ten’ or ‘hundred’ number is the closest for rounding and estimation?

1. Determine which two whole number powers of 10 a number falls between.
2. Determine the lowest and greatest possible number that a nice number has been rounded from. (A number was rounded to 60. What is the least possible number it could have been?)
3. Fluently add and subtract within 1,000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.

Procedures/Activities

1. Using the interactive whiteboard lesson, introduce the name of today's lesson and essential question (or objective for schools' that don't use an essential question.) (Slide 1)
2. Use the next page and questions to discuss estimation. (Questions are, "When you do math like adding and subtracting in your everyday life, do you always have to have an exact amount? Â—Can you think of a time when you don’t have to know the exact amount?") (Slide 2)
3. Along with students, discuss each scenario listed to decide whether an exact or estimate is needed. Make sure to ask students to justify their answer. (Slide 3)
4. Talk about nice numbers, what they are, and why nice numbers are easy to work with. (Slide 4.) This includes ideas like they are easy to compute both on paper and mentally.
5. Introduce Roll 'N Round Game. Go over list of materials and make sure they are distributed. (Slides 5)
6. Put students into pairs. It is ok if there is a group of 3.
7. Read directions one by one prior to playing game whole group. (See the teacher handout of the directions.) (Slide 6)
8. Model the game with the class using the interactive white board lesson. For the model, only 5 rounds will be done. Virtual Dice has 10-sided die that can be customized to digits 0-9. This page will be seperate from the IWB lesson. It must be set up prior to modeling. (Slide 7 & 8 and use virtual dice)
9. When model is over, let pairs begin game.
10. Teacher should monitor game play and observe student actions. Look for correct use of rounding.
11. As students finish, let each pair come to the board and write their names and circle the name of the winner. (For early finishers, let students continue playing on the back of the record sheet even if they do not get to finish.)
12. Follow-up discussion should include questions: "Looking at your record sheet, how much of this game is chance? How much is choice? What do you notice about the numbers where you had to go to the nice number that was less? What do you notice about the number where you got to go to the nice number that was most? What did you decide to do with the numbers that had a 5 in the ones place?"
13. Provide exit slip for students to complete at the end of the discussion.

1. Using the interactive whiteboard lesson, introduce the name of today's lesson and essential question (or objective for schools' that don't use an essential question.) (Slide 1)
2. Use the next page and questions to discuss estimation. (Questions are, "When you do math like adding and subtracting in your everyday life, do you always have to have an exact amount? Â—Can you think of a time when you don’t have to know the exact amount?") (Slide 2)
3. Along with students, discuss each scenario listed to decide whether an exact or estimate is needed. Make sure to ask students to justify their answer. (Slide 3)
4. Talk about nice numbers, what they are, and why nice numbers are easy to work with. (Slide 4.) This includes ideas like they are easy to compute both on paper and mentally.
5. Introduce Roll 'N Round Game. Go over list of materials and make sure they are distributed. (Slides 5)
6. Put students into pairs. It is ok if there is a group of 3.
7. Read directions one by one prior to playing game whole group. (See the teacher handout of the directions.) (Slide 6)
8. Model the game with the class using the interactive white board lesson. For the model, only 5 rounds will be done. Virtual Dice has 10-sided die that can be customized to digits 0-9. This page will be seperate from the IWB lesson. It must be set up prior to modeling. (Slide 7 & 8 and use virtual dice)
9. When model is over, let pairs begin game.
10. Teacher should monitor game play and observe student actions. Look for correct use of rounding.
11. As students finish, let each pair come to the board and write their names and circle the name of the winner. (For early finishers, let students continue playing on the back of the record sheet even if they do not get to finish.)
12. Follow-up discussion should include questions: "Looking at your record sheet, how much of this game is chance? How much is choice? What do you notice about the numbers where you had to go to the nice number that was less? What do you notice about the number where you got to go to the nice number that was most? What did you decide to do with the numbers that had a 5 in the ones place?"
13. Provide exit slip for students to complete at the end of the discussion.

1. Using the interactive whiteboard lesson, introduce the name of today's lesson and essential question (or objective for schools' that don't use an essential question.) (Slide 1)
2. Use the next page and questions to discuss estimation. (Questions are, "When you do math like adding and subtracting in your everyday life, do you always have to have an exact amount? Â—Can you think of a time when you don’t have to know the exact amount?") (Slide 2)
3. Along with students, discuss each scenario listed to decide whether an exact or estimate is needed. Make sure to ask students to justify their answer. (Slide 3)
4. Talk about nice numbers, what they are, and why nice numbers are easy to work with. (Slide 4.) This includes ideas like they are easy to compute both on paper and mentally.
5. Introduce Roll 'N Round Game. Go over list of materials and make sure they are distributed. (Slides 5)
6. Put students into pairs. It is ok if there is a group of 3.
7. Read directions one by one prior to playing game whole group. (See the teacher handout of the directions.) (Slide 6)
8. Model the game with the class using the interactive white board lesson. For the model, only 5 rounds will be done. Virtual Dice has 10-sided die that can be customized to digits 0-9. This page will be seperate from the IWB lesson. It must be set up prior to modeling. (Slide 7 & 8 and use virtual dice)
9. When model is over, let pairs begin game.
10. Teacher should monitor game play and observe student actions. Look for correct use of rounding.
11. As students finish, let each pair come to the board and write their names and circle the name of the winner. (For early finishers, let students continue playing on the back of the record sheet even if they do not get to finish.)
12. Follow-up discussion should include questions: "Looking at your record sheet, how much of this game is chance? How much is choice? What do you notice about the numbers where you had to go to the nice number that was less? What do you notice about the number where you got to go to the nice number that was most? What did you decide to do with the numbers that had a 5 in the ones place?"
13. Provide exit slip for students to complete at the end of the discussion.

Assessment Strategies

Use included Exit Slip. Students should try to complete without hundreds chart, but may use if cannot complete without it. Questions 1-4 are two-digit numbers that are direct use of the activity. Number 5 is an extension item which will determine if students can transfer understanding of two-digit rounding in a three-digit number. Number 6 is a higher-order, critical thinking question. The last problem is to see if students can apply rounding in a contextual problem with addition.

Acceleration

If students can already round with two-digit numbers or without a hundreds chart, they can still play the game. Either they can complete the record sheet without using the hundreds chart or have them roll three times to make a three-digit number and round to nearest ten. In both situations, they should continue to write the two nice numbers the rolled numbers fall between.

Intervention

Explore the hundreds chart.

Practice rolling die to make numbers.

Use a record sheet that does not require 10 rounds.

Total Duration

31 to 60 Minutes

Background/Preparation

Teacher

• Go to virtual dice webpage, choose a 10-sided dice, then customize dice. Teachers need to enter the digits 0-9 on the 10 sides.
• Set up laptop and interactive whiteboard for presentation of lesson.

Student

• Should be familiar with a hundreds chart.

Materials and Resources

Teacher:

• Interactive whiteboard lesson (If interactive whiteboard is not available, use attached teacher pages for overhead, dry-erase board, or chart paper.);
• Virtual Dice webpage prepared;
• Laptop connected to interactive whiteboard (If teacher does not have a laptop for presenting, content may be written on the dry-erase board or chart paper.); and
• Interactive white board (IWB) (If no IWB, teacher may use LCD with copies on transparency sheets, DE board or chart paper.).

Student:

Each student should have:

1. a hundreds chart;
2. Roll ‘N Round Record Sheet;
3. a sheet protector to place the hundreds chart in;
4. a dry-erase marker;
5. something to erase with (if sheet protector and marker are not available, students may use hundreds chart without writing on it);
6. pencil; and
7. exit card.

Each pair of students should have:

1. One dodecahedra die 0-9 (number cards 0-9 that can be shuffled can be used if dice are not available).

Technology Resources Needed

• LCD Projector
• Interactive Whiteboard
• SMART Lesson (If teacher does not have SMART software, this lesson will not open. Please refer to directions for using overhead projector, dry-erase board, or chart paper.)