plant growth

Hi folks,

Does anyone know of a site where they demonstrate the effect of prayer, or simply good thoughts towards plants, that show the effects graphically? 

I've seen somewhere photos (or was it videos?), but can't remember where.

I've been asked to give a talk (slide show) to celebrate Earth Day at the elementary school my grand-kids are going to.  I want to make it all nice and sweet (they'll get the horror stories in soon enough) and show them how all life (the biosphere) is connected by our emotions/thoughts and that we are part of it.