I used to use a whisper phone! DIY Whisper Phones~ Children use these to hear themselves as they quietly read aloud. This post has great directions and with pictures that explain how to make them with inexpensive materials.
15 strategies to help toddlers with sensory processing disorder and food aversions to try new food! Tips from a parent who has been there! * Not that my kids have this, but interesting approach to picky eaters.