It often happens to me that after learning the whole day and reading lots of text especially with small letters I feel my eyes very tired. Who knows good set of exercises that don't takes lot of time, that helps to prevent eyes tiring.
Here is a link to WikiHow on Eye Exercise to reduce eye strain: How to Exercise Your Eyes.
A Google search for "exercises to reduce eye strain" yielded many helpful results.
Please let us know if you have tried any of these and how they work.
Another page with eye exercises: http://eyepitstop.com