kids doing cleanups and collecting data
Register your cleanup        Pre-cleanup lessons and inspiration        Do your cleanup       

After the Cleanup

NGSS PRACTICES as They Relate to Planning, Data Collection, and Follow-up

This activity was adapted from Clean Shorelines, Clean Oceans, from Waves, Wetlands, and Watersheds
(View NGSS and CCSS connections for Clean Shorelines, Clean Oceans)

Back in the classroom, analyze the data collected at the cleanup:

  1. Decide how to tabulate the data, such as by location or time/date collected. This is best done through student discussion. Tabulation may be done as a homework assignment or it may be assigned to a designated student or students. Use spreadsheet software if available. NGSS Practices: Analyzing and Interpreting Data; Using Mathematics and Computational Thinking; Engaging in Argument From Evidence
  2. Divide students into small groups, each with its own segment of the data. Each small group will choose a method for organizing the data that attempts to answer the students' question(s). This might include organizing by material (plastic, glass...), by suspected activity (lunch, sports, transportation...), by the debris item or brand, or another method. Each small group will decide on a method for displaying the data from their data segment, such as pie chart, line graph, bar graph...Use spreadsheet software if available. NGSS Practices: Analyzing and Interpreting Data; Using Mathematics and Computational Thinking; Obtaining, Evaluating, and Communicating Information
  3. Have each group share their visual presentation of the data with the class. Allow for student questions after each presentation. NGSS Practices: Engaging in Argument From Evidence; Obtaining, Evaluating, and Communicating Information
  4. Guide a class discussion that may address the following:
    • Were the pre-investigation questions answered?
    • Is there a question that could be answered by repeating the cleanup and/or revising the method of data collection?
    • Was a particular method of displaying the data more or less effective? Did this change based on what aspect of the data was being displayed?
    • Do certain items indicate specific sources of debris? (For example, are there straws from a campus juice box vending machine?)
    • Why is it important to know the location of the debris and the date of the sampling?
    • Where does most of the trash accumulate?
    • Which items of debris do students think are the most dangerous to wildlife?
    • How does it make them feel to see the trash on their campus?
    • How does it make them feel to see the campus clean after their work? Was it still clean the following day?
    • How can the data that was collected be used by the students and others to reduce litter and waste?

    NGSS Practices: Analyzing and Interpreting Data; Constructing Explanations and Designing Solutions; Engaging in Argument From Evidence

Compare your data to data collected at other cleanup locations by visiting an international database maintained by the Ocean Conservancy at This map-based database includes data collected starting in 2016. You can browse the map or click on "View Reports" in the top right to filter your search results and download spreadsheets. In order to view data collected between 2008 and 2015, from the home page scroll down and click on "Access the Old System" under "View Reports." In the top left, click on "Change Period" to select the data collection time period. (If the site is down, please email us and we'll check in with the Ocean Conservancy.)

Depending on your location, it may be possible to compare your data to "up-watershed" and "down-watershed" cleanup sites, for example upstream of a nearby river as well as at the mouth of that river where it empties into the ocean. What similarities and differences can the students identify between their schoolyard cleanup and these other locations? Students may want to compare data from other parts of the United States or one of the many other countries that take part in the International Coastal Cleanup. Students can do similar analysis on this larger dataset as they did for their own data. NGSS Practices: Analyzing and Interpreting Data; Using Mathematics and Computational Thinking

You can enter your own cleanup data into this database! To do this, follow the directions on and identify your "group name" as your school name - Schoolyard Cleanup. (Adding "Schoolyard Cleanup" as part of your group name will make it easier to search for program participants within the database.) Please email us to let us know that you entered data, or if you need any help. You can also download the Ocean Conservancy's free CleanSwell app if you have the technology available and you'd like to bypass the paper datacards to enter data directly into the database. A link to the app store is found at the bottom of

What Next?

Preventing Pollution at the Source from Waves, Wetlands, and Watersheds has strategies for planning an action project with your students. (View NGSS and CCSS connections to this activity.) Your students are likely to have great ideas on how they can work to solve problems they identified through their cleanup. Some potential action projects might include:

  1. Read about 29 trash items that are often found during California shoreline cleanups, and how you can help eliminate them. Compare these items to those that were found in your Schoolyard Cleanup. Why do you think you did or did not find these at school? What can you do to address the items that were a problem at your school?
  2. Write letters and/or make presentations to the principal, student council, PTA, superintendent and/or school board about problems of litter and waste that you identified on your campus. Prepare and present proposals to reduce the litter and waste.
  3. Hold a "waste-free lunch" campaign, encouraging students to bring their own lunches in reusable containers. Find tips on waste-free lunches on our website. Be mindful of students who receive free and reduced-cost lunches at school, as it may not be within their control to pack a lunch. Presenting cafeteria waste reduction suggestions to the principal or superintendent may a good alternative if this is an issue for your students.
  4. Make a display (collage, sculpture, or representation) of the trash collected during your cleanup. This display may be artistic (beautiful or grotesque or...), it may be informative (with labels, charts...), or it may be both. Placing the display in a prominent place in the school can do a lot to educate the student body and staff.
  5. Write articles for the student or local newspaper about the cleanup and the data collected or create a video to share.
  6. Make presentations to other classes (or to classes at another school) about your cleanup and the data.

Repeating the cleanup after implementing a solution is a good final step in this project. Has the data changed? Was the solution a success? Can it be refined and improved for a better outcome? NGSS Practices: Constructing Explanations and Designing Solutions