Which Way to Mexico?
Do You Know?

Monarch butterflies are born knowing the way to Mexico — do you? Guess which way they should fly and, on the count of three, point in that direction. (Have each person put a "Post-it note" on the wall, to mark the direction of their guess.)
Mexico's monarch sanctuaries are west of Mexico City, at 19N, -100W.
(Click on map to see more.)

Try This!

  1. Take out a globe and find Mexico's monarch sanctuaries.
  2. Make and cut out a small paper "compass rose," with a diameter of about 6 cm. Carefully label north (0 degrees), east (90 degrees), south (180 degrees) and west (270 degrees) on the compass.
  3. Put the compass rose on the globe directly above your home town. (To ensure that the compass shows direction accurately, align its north/south axis parallel to the longitude lines at your latitude.)
  4. Place a ruler on top of your compass and, pivoting from the center of the compass, look below the ruler until it's lined up to make a straight line between your home town and the sanctuaries.
  5. Mark the place on the compass where the ruler intersects the compass. This reading is the "bearing" from your home town to the sanctuaries. For a closer reading, go back and fill in values on the compass to 10 degree increments.
  6. Use this bearing to mark the direction to Mexico in your classroom. Using a real compass, align it to north. Then take your bearing measurement with the compass. Draw an imaginary line to the classroom wall and mark the wall with a monarch carrying a little sign, "This way to Mexico" or "Mexico or bust!!"
  7. The next time you're outside with a real compass, find the direction to Mexico using your bearing measurement, and then point in the direction of the Mexican sanctuaries.
  8. Finally, the best part: Lie down on your back and watch for migrating monarchs. Are they flying in the same direction you calculated?

    If they're not, don't be surprised! You'll have uncovered one of the greatest mysteries of the monarch migration.

    How Do They Do It? What Scientists Say
    How DO monarchs orient and navigate to a small point on the globe--to a place they've never been before? Scientists don't fully understand the mechanisms involved. Read the excerpts below and have students list factors scientists believe (or once believed) are involved. Next, ask students to list questions scientists still have.

National Science Education Standards

  • Employ simple equipment/tools to gather data and extend senses. (K-4)
  • Use appropriate tools and techniques to gather, analyze, and interpret data. (5-8)
  • Although men and women using scientific inquiry have learned much about the objects, events, and phenomena in nature, much more remains to be understood. Science will never be finished. (K-4)

National Geography Standards

  • How to use maps and other geographic representations, tools, and technologies to acquire, process, and report information.