Sure enough, there was a shelled critter, being very social, and with great speed, making the rounds to check out the circle of children that soon surrounded him!
We soon found out that "Franklin", as the tortoise was aptly named, belonged to a neighbour who had decided to take him out for a walk in the afternoon sun. Franklin was rather enjoying the attention, it seemed, and I had to fairly pry the class away from him, so that we could return to the school before the end-of-day bell rang.
What a delightful and unexpected experience!