Monarchs and Their Decline

About This Lesson

This lesson introduces students to the recent population decline of monarch butterflies, including their anatomy, life cycle and migration patterns. Students will interpret a graph showing monarch population decline throughout the last several years. Although students will not be working with monarch butterflies, this provides an interesting segue into common milkweed, the food of choice for monarch caterpillars.



After this lesson, students will be able to:

  • Discuss the monarch life cycle and migration patterns
  • Interpret a line graph, and
  • Discuss overall trends in monarch population decline.

You may also wish for students to be able to make arguments about why people care about the fate of monarchs (and milkweeds).


Information for Classroom Use:

Students should know or be familiar with:

Components of a line graph such as the x- and y-axis, units, etc.

Teachers should know or be familiar with:

Definitions of “anthropogenic,” “biotic,” and “abiotic” causes for changes in an ecosystem

Reasons people care about monarch populations. For example, monarch populations are connected to many other organisms, like predators, pollinators, and competitors. Biodiversity in general has value that can’t be linked to any individual organism. The monarch migration is an amazing phenomenon with cultural significance. The monarch decline is related to many complex human problems, and learning to solve one will help us solve others.



Approxiamte duration for the the task is 30 mins or half of a class period.

  • Computer with internet and projector capabilities
  • Large sheet of paper or word processing software



See Grade Versions of This Lesson

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