Host a bean race.Students will determine the rate of growth of pole variety bean plants and award the fastest plant a blue ribbon.

Grade level: Upper Elementary-Middle School

Length of lesson: 1 hour a week for 1 to 2 months, depending on where you are in the growing cycle of your bean plants.

### Materials

- Access to the school garden
- Grade appropriate measuring tools such as rulers, yardsticks, meter sticks, and measuring tapes
- Step stool or ladder for measuring tall plants
- Numbered labels for each plant
- Clipboards
- Writing utensils
- Bean Race Worksheet
- Blue ribbon for winning plant

### Student Objectives

- Students will accurately measure the height of bean plants over several weeks
- Students will determine rate of growth for each bean plant
- Students will determine the plant with the fastest rate of growth to declare a winner
- Students will brainstorm reasons why some plants grew faster than others

### Common Core Standards

CCSS.MATH.CONTENT.2.MD.A.1

Measure the length of an object by selecting and using appropriate tools such as rulers, yardsticks, meter sticks, and measuring tapes.

CCSS.MATH.CONTENT.3.OA.A.3

Use multiplication and division within 100 to solve word problems in situations involving equal groups, arrays, and measurement quantities, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem

CCSS.MATH.CONTENT.3.OA.C.7

Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties of operations

CCSS.MATH.CONTENT.3.MD.B.4

Generate measurement data by measuring lengths using rulers marked with halves and fourths of an inch. Show the data by making a line plot, where the horizontal scale is marked off in appropriate units— whole numbers, halves, or quarters.

CCSS.MATH.CONTENT.4.MD.A.2

Use the four operations to solve word problems involving distances, intervals of time, liquid volumes, masses of objects, and money, including problems involving simple fractions or decimals, and problems that require expressing measurements given in a larger unit in terms of a smaller unit. Represent measurement quantities using diagrams such as number line diagrams that feature a measurement scale.

CCSS.MATH.CONTENT.4.MD.B.4

Make a line plot to display a data set of measurements in fractions of a unit (1/2, 1/4, 1/8). Solve problems involving addition and subtraction of fractions by using information presented in line plots.

CCSS.MATH.CONTENT.5.MD.B.2

Make a line plot to display a data set of measurements in fractions of a unit (1/2, 1/4, 1/8). Use operations on fractions for this grade to solve problems involving information presented in line plots.

CCSS.MATH.CONTENT.6.RP.A.3.B

Solve unit rate problems including those involving unit pricing and constant speed

CCSS.MATH.CONTENT.6.EE.C.9

Use variables to represent two quantities in a real-world problem that change in relationship to one another; write an equation to express one quantity, thought of as the dependent variable, in terms of the other quantity, thought of as the independent variable. Analyze the relationship between the dependent and independent variables using graphs and tables, and relate these to the equation.

### Instructional Plan

**Introduce the Lesson**

- During your unit on rate of change or measurement, tell students that the will be conducting a race! Explain to them that as a class they will be measuring the height of bean plants to determine which plant is growing the fastest.
- Determine how many weeks you will be taking measurements.
- Discuss what unit measure you would like them to use for the project and review how to use the measuring tools.
- If the plants are taller than the students review stepladder safety and procedures.
- With your garden manager, create numbered labels for each bean plant.
- Evenly divide the class between the number of bean plants in the garden.

**Procedure**

- Pass out a copy of the Bean Race worksheet to each student
- Have each student record their name and the number of their plant at the top of the worksheet.
- Have each student record the starting date at the top of their worksheet.
- Bring students out to the garden and have them measure and record their initial height for their plant. Have each student in the group take a measurement and have them compare their findings until they can agree on the exact height.
- Once a week, bring students out to the garden to take accurate measurements of the bean plant height. Each time have the student record the date, current height of their plant and the change in height from the last time they measured.
- At the end of the unit, use the formula at the bottom of the page to determine the rate of growth for their plant. Have students compare their finding with their group members to check each other’s work.
- Compare the finding of the entire class to determine the “winning” plant.

### Extensions/Celebrations

- Decorate the winning plant with a Blue Ribbon!
- Discuss as a class and have students create hypothesis as to why some plants grew faster than others.
- Have students test their hypothesis in the winter using indoor plants under the different conditions discussed.

### Assessment Considerations

- Were students able to take accurate measurements?
- Did students accurately record their data for each session?
- Were students able to show their work in all equations?
- Were students able to accurately determine the difference in height for each session?
- Were students able to accurately determine the rate of growth for their plant?