wow. Whatever I was about to comment on, Simone already did it and pretty much said what I was about to :o
Anyways, here is some other stuff that I found.
They listened to their daily lessons with open ears, and open hearts. I felt enlightened. Who would have known that just a few hours of my time could have such a profound affect on people?
^Why did you feel enlightened? Or even better. How?
If anything, I would have assumed it was the children who felt enlightened?
Also, it is 'effect' on people.
And who knows that is even a profound effect? Revise, cause otherwise, it sounds as if you are flattering yourself, even though you are talking about the preaching of spirituality and religion, which I believe advocate modesty.
I now strive to make others happy, for seeing a smile in return is the best reward I can ask for.
^Best reward? I liked your previous sentence, but I do not think that this final one does justice.