Monarch Population Decline Debate

About This Lesson

This lesson will revisit the information students already know about monarch butterflies and common milkweed plants. Using excerpts and summaries of research papers on the declining monarch population, students will debate the most likely cause of the decline and compare arguments from experts in the field.



After this lesson, students will be able to:

  • Identify multiple potential causes for the monarch population decline.
  • Compare the strengths and weaknesses of each potential cause.
  • Understand that biology is an ever-changing field; there is not always one “right” answer, and biologists disagree and use evidence to argue about explanations for phenomena, like the decline of monarch butterflies.

Information for Classroom Use:

Students should know or be familiar with:

  • Their individual and class lists of factors that might be related to monarch population decline

Teachers should know or be familiar with:

  • The Claim, Evidence, Reasoning framework (see Youtube Video for a detailed example)

This lesson is about 50-60 minutes or one class period.

Previous class list of potential reasons for monarch decline (either electronic or hard-copy)

See Grade Versions of This Lesson

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