I must say the lateral /sh/ used to scare me a bit in speech therapy until I took Pamela Marsalla’s course,“Practical Therapy Tips for Persistent Articulation Errors: Frontal Lisp, Lateral Lisp and Distorted R. I got amazingly quick results in establishing a correct /sh/, without the lateral emission of air, by applying her techniques with a 4 1/2 year-old student of mine. He responded well to using a nice big Duncan Donuts straw to capture the airflow out the front of his lips instead of the sides, holding the position for the E and breathe through it for /sh/ and getting feedback from physical prompts (from PROMPT).
We were adding to one of his favorite games, “Race to the Treasure” by Peaceable Kingdom, using some figures from “Jungle Book.” Suddenly, my little friend said, “Look at Mowgli’s shadow!” Nice /sh/ word!! Sure enough, Mogli and his bear friend were casting long shadows on the game and provided a nice practical way to practice his /sh/. We went with this and moved our figures around to get longer and shorter shadows and described them. Everybody needs a little variety once in a while!