This lesson uses the topic of cell phone service to illustrate how government and the economy are related. Students learn the difference between market, command, and mixed economies. Building on the idea of a mixed economy, the lesson discusses government limits on economic activity, including anti-trust laws, tariffs, and consumer protection. Having studied cell phone service as an example, students apply what they’ve learned by showing how the principles of a mixed economy work in the food production industry. Teacher Resources. Get access to lesson plans, teacher guides, student handouts, and other teaching materials.