Despite having experienced many Hudson Valley springs, I'm still awed by the trees and flowers.

And, with a high school senior in the house I'm more aware than ever of how challenging this annual bursting-out must be for teachers trying to keep kids' attention.

One possibility may be to change things up a bit and get outside.

Has anyone tried Leafsnap? It's the first in a series of electronic field guides being developed by researchers from Columbia University, the University of Maryland, and the Smithsonian Institution.

The free mobile app uses visual recognition software to help identify tree species from photographs of their leaves.

To complement the technology, check out two lessons in THV's on-line library --

Tree Identification by Arlington elementary teacher Jason Venier, and

Balancing the Water Budget of a Leaf from the Cary Institute of Ecosystem Studies. Both were designed for grades 3-6, but could be adapted.

Remember, you must be registered and logged in to get materials associated with the activities.

Please let us know about your experience with Leafsnap or these lessons. And, while you're at it, do you know what trees these pictures come from?