I had a great moment the other day in the Roma mobile school. We have been reviewing the dozen or so letters that the students have already learned (I, T, O, C, A, etc) but it didn't seem like the letters were sticking in anyone's head. We would do a whole worksheet on the letter T (as a review, T was already taught before), but then five minutes later no one could remember how to write the letter T.
But while I was working with Tino to write the word "biciklo" and told him, while sounding it out, that the third letter is "C", he started to say, "how do you write---" and then let out a gasp and wrote the letter C himself. I think he was shocked to realize that he actually knew how to write it, and frankly, so was I. That was the best thing that happened to me all day.