C. Talk to the person running the program, say you hate to complain, and finish it from there?

Talk to the person and express how much Ana enjoyed the previous structured method. Its important that you emphasize Ana, rather than yourself, because you assume the coordinator wants the program to be succesful fromn the toddlers' point of view. If that fails to elicit change, then you are justified in escalating to their boss, etc., as long as you are always keying on the toddlers' experience.

Option B is too much like gossiping, and Option A, from what I've seen of you (at least online) isn't really an option, is it?