Mrs. Hyatt was a the Speech Therapist at my elemetary school. I had a lisp, and in third grade I was told to go every Tuesday to a small trailer at the back of the school. In this trailer I would sit with Mrs. Hyatt and practice my 's' and 'z' sounds until I could thay, I mean say them properly. I got star stickers on each level of sounds that I made.
I still lisp sometimes, but only when I'm excited or angry.