This advice-column-style blog for SLPs was authored by Pam Marshalla from 2006 to 2015, the archives of which can be explored here. Use the extensive keywords list found in the right-hand column (on mobile: at the bottom of the page) to browse specific topics, or use the search feature to locate specific words or phrases throughout the entire blog.
Q: My client has no back sounds, and he substitutes Sh and Ch for S. I cannot get a good S out of him. I have tried straws and the Ts technique you talk about, but he always makes a Sh or Ch. What do you think I should try next?
I think you should try putting more attention on his tongue-tip to stimulate S and Z.
The following excerpt about improving awareness and control of the tongue-tip is from The Marshalla Guide. It will be in the chapter called “Facilitating Tongue Movement”––
Dental Floss and Dental Pick for /S/ and /Z/ Groove
Dental floss or a dental pick can be used to teach a client how to create the minute central groove needed at the tip for production of /s/ and /z/––
- Knotted dental floss: Vaughn and Clark (1979) described this method. They said to tie a bundle of knots at the end of a piece of dental floss 15-inches long. Place the floss between the upper central incisors and pull it so that the knots sit on the lingual surfaces of the upper central incisors right at the juncture between the teeth and alveolar ridge. Teach the client to reach the tongue-tip up to the knot and tickle it with his tongue-tip. Then teach him to blow a tiny bit of air against the knot as he does so and a sound nearly like /s/ will result.
- Interdental picks: The above technique can be done with a dental pick today. Place the pick between the upper central incisors so that its tip pokes between them. The tip of the pick will stick out behind the upper central incisors and sit between the tongue-tip and the alveolar ridge. Teach the client to reach the tongue-tip up to the pick and tickle it with his tongue-tip. Then teach him to blow a tiny bit of air against the tip of the dental pick and a sound nearly like /s/ will result.
- Vaughn, G. R., & Clark, R. M. (1979). Speech Facilitation: Extraoral and Intraoral Stimulation Technique for Improvement of Articulation Skills. Springfield: Charles C. Thomas.