When I told them I had the letters the atmosphere in class changed and I could feel enthusiasm, happiness, and my students' wish to open and read them.
After having got their letters the students started reading them and enjoyed having info about their Spanish friends. They also liked the decorations and the drawings on the letters a lot. The students were proud of their letters and showed them to their school mates.
I asked them to start writing a reply and they didn't let me repeat it: they started at once. Some of them Had time to do it at school and some other promised to do it at home. They asked me for idiomatic expressions or more complicated words, they used the dictionary and so they created their answers to be sent to their friends.