Earth Day falls on Thursday, April 22, 2027. For high school students, the best Earth Day lessons go beyond picking up litter: they use data, investigate local problems and end with an action students can measure. These Earth Day activities for high school work across science, math, social studies and English.
In this guide8 sections
Quick background
- The first Earth Day was held on April 22, 1970 in the United States, organized as a national teach-in on environmental issues.
- Later that year, the U.S. Environmental Protection Agency (EPA) was established.
- Earth Day became international in 1990 and is now observed in many countries.
Science activities
- School waste audit. With gloves and supervision, groups sort one day of classroom trash into recycling, compost and landfill, weigh each category and graph the results.
- Water quality testing. Test tap water or a local stream for pH and temperature and compare results.
- Carbon footprint calculator. Students estimate their household’s energy and travel footprint with a free online calculator and identify the biggest category.
- Greenhouse effect model. Compare temperatures in two covered and uncovered jars under a lamp and explain the difference.
- Energy transformation lab. Our Energy Skate Park lab connects energy conservation to real-world energy use.
- Local species survey. Students photograph and identify plants, insects and birds on school grounds.
Math and data activities
- Graph the waste audit. Turn audit data into bar graphs and percentages, then calculate how much waste the school produces in a year.
- Energy bill analysis. Use a sample electricity bill to calculate cost per kilowatt-hour and the savings from switching bulbs.
- Water use estimate. Students track showers, dishes and laundry for a day and estimate weekly water use.
- Climate data trends. Plot a public temperature dataset for your region and describe the trend.
Social studies and English activities
- History of environmental laws. Groups research the Clean Air Act, Clean Water Act or Endangered Species Act and present what each changed.
- Persuasive letter. Students write to a local leader or school administrator proposing one environmental change, supported by data from the audit.
- Debate. Assign sides on a local issue, such as a new park versus parking lot, and hold a structured debate.
- Environmental writers. Read a short excerpt from an environmental author and discuss its argument.
Action projects
- Classroom recycling system. Students design clear bins and labels based on the waste audit.
- Energy patrol. A student team checks that lights and devices are turned off after school for a month. It fits well with classroom jobs for high school.
- School garden or planters. Start a small native-plant garden or windowsill planters.
- Awareness campaign. Students create posters or short videos with one specific, measurable message.
Planning table
| Time available | Best picks |
|---|---|
| One class period | Carbon footprint calculator, energy bill analysis, greenhouse jar model |
| Two periods | Waste audit plus graphing, persuasive letter |
| Earth Week or longer | Recycling system, energy patrol, school garden |
Tips for a strong Earth Day lesson
- Use real data from your school or town; local problems feel more urgent than global statistics.
- End with one action students can measure, and check the result a month later.
- Keep the tone hopeful and practical rather than overwhelming.
- Use group roles to keep projects organized; see our guide to group work roles.
Frequently asked questions
When is Earth Day 2027?
Earth Day is Thursday, April 22, 2027.
What are good Earth Day activities for high school?
Waste audits, water testing, carbon footprint calculations, data graphing, persuasive letters and action projects like a recycling system work well for teens.
When was the first Earth Day?
The first Earth Day was April 22, 1970, in the United States. It became an international event in 1990.
Pick one investigation, one data activity and one action project. Students leave Earth Day with evidence, a plan and a reason to keep going. For more seasonal ideas, browse our seasonal activities.
Plan the whole year with our classroom activities calendar 2026–2027.
