How Does Your Garden Grow? (8th Grade)

Part 1: Assessing Soil Chemistry

Display slide 8 and draw students’ attention to the soil samples. Inform students that they will be analyzing each soil sample using common soil chemistry tests. Explain to students that they will be testing the soil pH as well as the nitrogen level, phosphorus level, and potassium level.

Show slide 9 and explain the process for preparing the soil samples.

Begin by having students create the soil solution. Instruct them to add 100 mg of soil and 200 mL of water to a beaker or other container. Ensure that they measure both the soil and water correctly.

Instruct students to stir the mixture using stirring sticks or rods. Ensure that students use a new or different stirring utensil for each soil sample.

Once each mixture has been prepared, allow them to sit overnight.

In the following class period, resume the lesson by displaying slide 10. Review portions of the lesson from the previous class period and stress to students that soil is important to plant health.

Pass out one copy of the Soil Investigation handout to each student. Additionally, provide each student with a Soil Hand Texture handout to assist them with the texture portion of the soil investigation. A copy of the Soil Investigation table can be seen below.

Explain the procedure for testing soil samples. This procedure may vary based on the types of soil test kits you purchased. Review the specific directions with students. Tell students that they should dip their test strips into the sample solution, allow 50–60 seconds for the test strip to change color, then compare the color of the test strip to the color chart. Tell them that each measurement should then be recorded in their Soil Investigation tables.

Tell students that they should document their process and results as they test the samples. They may do this by taking photos using tablets or their phone camera, if your classroom allows student devices. Explain to students that they will incorporate these pictures in their final presentations.

Instruct students to begin testing their soil samples. As they test the samples, walk around the room and assist students with the testing process. Answer any questions they may have and guide them in making observations about their samples, if necessary.

After the testing process is complete, display slide 11 and explain the clean-up process.

Part 2: Investigating Soil Health

Display slide 12 and introduce the next part of the lesson to students. Explain that students will explore several online resources to learn more about soil properties and soil health.

Transition to slide 13 and pass out the Window Notes handout to each student. Tell students that they will explore resources about soil health in a Wakelet. As they read each source, they will take Window Notes over soil health, but will leave the Nutrient Cycles portion of the handout empty. Direct students to access the Explore Sources Wakelet and begin reading through the resources.

Part 3: Discussion

After students have read the sources, display slide 14 and introduce the discussion portion of the lesson. On the class board or on a large sheet of paper, create an Anchor Chart for each quadrant of the Window Notes. Consider including diagrams or drawings of soil horizons as part of the chart.

Display slide 15 and begin a class discussion on students’ window notes. Use the following questions on the slide to guide the discussion:

• What is soil?

• How do we describe soil?

• How do we know if soil is healthy?

• What are the benefits of having healthy soil?

• What soil management practices or strategies would improve soil health?