Activity 1: Introduction

1. Following the Interest Approach students should begin to have an idea of the significance of the projected population growth in our world. Ask students to begin thinking about the overall impact of population growth as they watch the video, Agriculture is Under Pressure.
2. Following the video, ask the class what the overall message is or what stuck out to them. Lead the discussion to conclude that farmers need to produce more food using the same resources.
3. Introduce the word efficiency. Discuss the definition and give real-life examples of efficiency that students will relate to. Point out that farmers will need to be more and more efficient to keep up with the demand for food.
4. Ask students what type of resources farmers need in order to produce our food. As you discuss the following resources, point out that they are limited. We can't obtain more. Therefore, we need to be more efficient in our use of them.
   • Open space to grow crops or raise livestock
   • Water
   • Arable soil (soil containing adequate nutrients, a proper growing climate, and appropriate soil texture for plant growth)
5. Point out that farmers have become more efficient in previous years through the use of technology. Ask students, "What are some examples of technology that farmers are using today?" (Students may discuss GPS, maps, cell phones, automated irrigation systems, computers, large machinery (tractors) with automated features, etc.)
6. Introduce the concept of precision agriculture. Explain that precision agriculture implements various technological instruments to make agriculture more precise and efficient. As an example show the video clip Kinze Autonomy Project: Harvesting System. As the video clip plays ask students what they notice is different about the tractor (there isn't a driver.) Explain that this tractor is operated using robot and GPS technology. This allows a single worker to harvest an entire field.
7. Introduce a second example of precision agriculture, variable rate application or (VRA). With VRA, different rates of an input such as water, seed, or fertilizer can be applied to a field to match the needs of each specific area. Show the video clip, Precision VRI: Make Every Drop Count to explain and illustrate the detailed technology that can be used to manage irration systems.
8. Following the video, summarize why farmers would want to use variable rate irrigation.
   • Increase crop yields. Too much or too little water decreases plant health and crop yield.
   • Conserve water.
   • Provide exact and precise watering for each soil type and slope within a field. (Soil type can vary within a field. Clay soil holds high amounts of water which allows the roots to soak in the water for a longer time. In sandy soils, water can quickly run through the soil without penetrating the roots).
     • Use slide 2 of the Increasing Production with Precision Agriculture PowerPoint to give clarification on how soil type affects water holding capacity.
     • Use slide 3 to show a picture of a field being watered uniformly. Ask students if they can see a section of the field that needs more water.
9. Use slides 4-7 to summarize key points in preparation for the next activity.

Activity 2: Calculating WUE and Building a VRI System

1. Give each student one copy of the Increasing Production with Precision Agriculture student handout.
2. Complete "Part 1" of the handout. This section can be completed as a class, in groups, or individually. Slides 9-19 walk through the worksheet step-by-step.
3. Move on to "Part 2" of the handout. Guide students through the instructions for the variable rate irrigation activity in the student handout. Using slides 20-25, explain to students that they will build a device to vary water flow (just like in variable rate irrigation). Their goal is to build a system to divide 16oz of water into three cups with 2 oz., 6 oz., and 8 oz. of water in each.
4. Form students into groups of three. Distribute a 16 oz. water bottle, 3 cups, scissors, and a choice of straws or other materials to each group.
5. Using slide 25, discuss the engineering design process with students and have them complete page 4 of the handout.
6. Give students 10 minutes to construct a device to simultaneously divide the water into 3 different amounts. Allow students to test their design and share it with the class.
7. After their designs have been tested, instruct students to complete page 5 of their handout.