Preschool Express: The Alphabet. Creative Teaching Press. $14.95. Here is an introduction to the ABCs that goes a step further than the exemplary "Sesame Street" alphabet video. Encouraged by a silent clown named Choo-Choo and a patient offscreen narrator, the young ones are encouraged to do as well as watch . An accompanying workbook--also incorporated into the video in leisurely page-by-page fashion--provides such activities as coloring, tracing and pasting stickers. Choo-Choo doesn't pack the charisma of Big Bird, which is fine: Perhaps viewers will pay more attention to their work. Information: (714) 892-5523.