Here are some ideas for earning the Eyes badge. Some activities are designed to be done in a patrol or unit, others are designed to be done at home.
Suggestions have been split into ideas for Guides aged under 10 and Guides aged over 10, but feel free to mix and match - as long as it is a challenge for the individual girl!
Play Kim's Game with your unit or patrol.
Learn about optical illusions and show some to your patrol. There are some good examples here.