Short "a" sound:
* arm
* barn
* calm
* carve
* dart
* farm
* harm
* jar
* march
* part
* sharp
* start
Note: The vowel sound in "charm" is a bit more complex than a pure short "a". It's often described as a "short a" with a slight "r" coloring. So, while the words above have a similar sound, they might not be an exact match.