Third Grade – Mathematics

3.OA.8: Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.

3.NBT.2: Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.

Lesson Time: 40 minutes

Materials: pictures of items for sale, 12 discs per student, copy of What is My Oportunity Cost worksheet.

This activity is a simulation game which involves students in the process of ordering school supplies and paying for them.

The students will each receive 12 discs, which the teacher has cut from construction paper. These discs will represent money.

Items for sale, and which are arranged in a display with their prices, are as follows.

School pencils | 2 discs |

Fancy pencils | 4 discs |

Lined newsprint paper | 1 disc |

Better quality paper | 3 discs |

Crayons (8 per pack) | 4 discs |

Crayons (16 per pack) | 6 discs |

Crayons (24 per pack) | 8 discs |

Eraser | 2 discs |

Marker set | 10 discs |

Distribute pictures of the items for sale and let the students color them and cut them out.

Items For Sale (pdf)

The students should individually decide with items they want to order. After ranking the pictures of items according to choice, the number of required discs can be grouped by the pictures.

Gather the pictures of all unordered items and discuss the choices made by the students.

Suggested questions for class discussion:

- What items do we need to work in school?
- What items would it be nice to have?
- Did anyone order 5 items?
- Did you order everything you need?
- Did you spend all 12 discs? If not, how many did you spend?
- Did you have enough discs to buy everything you wanted? If not, how many discs would you need to buy everything you want?

What is My Opportunity Cost Worksheet (pdf)

Third Grade – Mathematics

3.OA.8: Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.

Lesson Time: 30 minutes

Materials: paper and pencil, ads for toys.

Let the students pretend that they are going to buy a new paint set. After reading all the ads in the newspaper, they learn that the item they want is being sold at the following stores for the following prices:

Store | Price | Location |

Store A | $4 | Five miles away and parents would need to drive. |

Store B | $2 | Three miles away and parents would need to drive. |

Store C | $1 | Two blocks away and student can walk. |

Store D | $3 | One block away and student can walk. |

Ask students if it will cost anything for Mom or Dad to drive to the different locations. Assume that it costs .25 per mile to drive. Ask students to rank the stores from least to most expensive.

Also, help them to consider the value of the time involved for themselves, as well as their parents.

Store | Price | Price to Travel | Total Price |

Store A | $4 | Five miles @ .25 = $1.25 | $5.25 |

Store B | $2 | Three miles @ .25 = .75 | $2.75 |

Store C | $1 | Two blocks away and student can walk = FREE | $1.00 |

Store D | $3 | One block away and student can walk = FREE | $3.00 |

Answer for ranking least to most expensive: Store C, Store B, Store D, Store A

Lead students to discover that the best buy is Store C when they consider all the factors involved.

Third Grade – Mathematics

3. OA.8: Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding. (This standard is limited to problems posed with whole numbers and having whole-number answers; students should know how to perform operations in the conventional order when there are no parentheses to specify a particular order.)

3 .NBT.2: Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction (A range of algorithms may be used.)Lesson Time: 40 minutes

Materials: Weekly Budget Workpage, computer to access Heather Learns About Earning, and Tim’s Turn to Learn.

After viewing Heather Learns About Earnings and Tim’s Turn to Learn complete the following worksheets on budgeting.

Sample Budget with Questions (pdf)

Third Grade – Mathematics

3 NBT 2: Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction. (A range of algorithms may be used.)

3NBT 3: Multiply one-digit whole numbers by multiples of 10 in the range 10 – 90 (e.g., 9 x 80, 5 x 60) using strategies based on place value and properties of operations. (A range of algorithms may be used.)

3.OA.8: Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.

Lesson Time: 30 minutes

Materials: Make a Plan. Start a Budget! Workpage for each studentIs there something your students want that requires money? Is it a new book, a bicycle, a Gameboy®, a vacation, or something else? Help your students use the planner to figure out how to budget their money and plan for the things that they want and need.

Students will need to have an understanding of what “needs” and “wants” are.

Student Magazine pages and worksheets: Make a Plan. Start a Budget! (pdf)

Third Grade – Mathematics

3NBT 2: Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction. (A range of algorithms may be used.)

3NBT 3: Multiply one-digit whole numbers by multiples of 10 in the range 10 – 90 (e.g., 9 x 80, 5x 60) using strategies based on place value and properties of operations. (A range of algorithms may be used.)

Lesson Time: 30 minutes

Materials: paper and pencil, chart paper

Ask students to carefully consider some future wants and then list the one that they would obtain first. Have students also list the cost of the item.

Have students pretend that they are getting $2.00 allowance per week. Ask them to figure out how long it will take before they can have the item they want.

Have students pretend that they are getting $5.00 allowance per week. Ask them to figure out how long it will take before they can have the item they want. Compare the difference between having a $2.00 allowance and a $5.00 allowance. In a class discussion ask students if the item is worth the amount of time needed to save the money to purchase it. Why?

Third Grade – Mathematics

3.MD.3: Solve problems involving measurement and estimation of intervals of time, liquid volumes, and masses of objects.

3. Draw a scaled picture graph and a scaled bar graph to represent a data set with several categories. Solve one- and two-step “how many more” and “how many less” problems using information presented in scaled bar graphs.

Students will compare sets of coins and determine which group is greater than, less than, or equal to the other according to the number and value of each set. Students will read and interpret a simple bar graph to answer questions.

Complete Lesson Plan (pdf)