# Area and Square Feet -- Out Teach

## Overview

In this lesson, students in this lesson will learn about, connect, and apply the use of the area to a real-world problem—creating a planting guide for the garden. Students will determine the square footage of the garden and use this information, along with a planting chart to create their own plan.

Background for instructors:

Math in the REAL world: Area and square feet

Square foot gardening is one way that ensures a vegetable garden bed can thrive. It is used to ensure not too many plants of a specific variety are planted in a single area. Using the square foot model keeps plants properly spaced, providing a perfect real-world context to teach area, apply multiplication strategies, and have students work collaboratively. Most garden beds are 8 x 4 resulting in 32 square feet to work with. It is possible however to have beds of different sizes. While 32 square feet to work with is what is used in this lesson, the methods and chart can be used for any rectangular planting area.

# Set up

The teacher should determine if this lesson will be used hypothetically or if students will follow through using their plans. If the latter is true, review the "extensions" activities.

The square foot garden bed chart used in the "explain" section can be drawn in advance on chart paper or on the white board.

# Engage: How to Determine Area of Planting Space

Gather students around a rectangular planting area or garden bed.

**Ask:** If you could plant any vegetable in the garden, what would you choose?

Quick turn and talk.

**Ask:** Let's say we only wanted to plant carrots. How many do you think you could plant in this space? How could we figure that out?

Accept answers.

**Ask:** What if I told you that knowing the area of the garden bed could help you figure this out? Today you will use this knowledge to solve a "real world" problem.

Review area and how it is found (L x W).

Explain that they will be making a vegetable planting plan using their knowledge of area.

# Explore: Vegetable Bed Area

Explain that students will be placed into teams to determine the area of the vegetable beds. They must work as a team to find the area using the tools provided.

Organize students in teams and give time to measure the length and width of a vegetable bed in feet.

**Management Note:**

Review boundaries, teamwork expectations and signal to return to the gathering space.

Circulate to various groups. Listen for misconceptions, ask questions to guide, but do not give the answers.

Ex: If we are measuring the width of this, where would I place the ruler?

Ex: How do you know this is the length?

Ex: I see you are measuring the total length around the bed. What does that tell us?

Students must record the multiplication of LxW in their journals.

Differentiation Note:

• Struggling students can use a multiplication table for facts and rely on team members

• Students who need a challenge can convert the measurements to inches and/or cm.

• This direction can be given in advance of the explore, or as the teacher circulates.

# Explain: Carrot Planting and Area

Gather students back to the central location.

**Ask:** What was the area of the planting space you measured? Share with a partner from a different group.

Use student measurements to demonstrate multiplication.

Model various methods of multiplication based on student use of these methods. Emphasize that length and width can be switched and still produce the same answer. Emphasize vocabulary of factors and products.

Draw out, or post a chart of a vegetable bed cut into the 32 squares in square foot gardening and explain that each square is one square foot which can be written as 1ft.2

**Ask:** Why do you think we call this a square foot? How does knowing the area help us determine the number of square feet we have to work with? What do you think the "2" represents when writing square feet?

Explain that this is important if we need to add fertilizer or mulch or to know how much space a certain plant might need.

Hand out and/or post the attached square foot planting guide and give them time to look over it.

**Ask:** How many carrots can be planted in 1ft.2 ?

Differentiation note:

• Vary question difficulty as needed. Examples include:

• How many spinach plants can be planted in 6 ft2 ?

• If carrot seeds cost $1.25 each, how much would it cost to plant a square foot?

• If 4 pole bean plants yield, 50 beans, how many square feet should be planted for a yield of 1,000 beans?

# Elaborate: Planting Plan

Teams will use their calculation, as well as the planting chart, to create a planting plan for a raised bed.

Have them draw out configurations of boxes, list the area in square feet, pick a plant that they would use for that space and multiply to determine the number of plants they will need.

Students can extend this to plan for the entire bed, or a fraction of a total bed.

Model as needed, or choose a student to model.

# Evaluate: Plans for Raised Beds

Student planting guides can be used as an informal evaluation of the concept.

Students should share their plans for the raised beds.

For individual evaluation have students replicate it in their journal.

Close by again emphasizing the importance of multiplication fluency for solving "real world problems" and congratulate students for using their math skills to create a planting plan.

# Extension Ideas

Complete the activity using cm instead of inches.

Or

Students can use the measurements and instructions on fertilizer to determine the amount of fertilizer necessary.

Or

Students can determine the amount of soil needed using extending from area to volume.

Or

Advanced applications could involve negative space. For example: How much mulch would we need if we mulched all around the beds but not inside them?

Or

Students could create a planting plan based on a specific recipe. The recipe could tie to one that shows is part of a reading anchor text, or one that gets at nutrition goals.

Or

Students could make a planting chart based on nutritional value, vegetable yield needed to sell at a school-based farmers market.

Or

Students could use nutrition value charts to make the "most" nutritious garden based on a specific vitamin or mineral goal.