my 2006 toyota corolla won't start even though battery is fully charged.

I agree, that it sounds like the starter. If the starter has a solenoid attached to it and your husband banged on that part, it could be the solenoid; however, it could also be loose connection to the starter and it was moved in the process. Most likely from your description though, you need a new starter (solenoid may also be included as part of the starter assembly). My suburban did the same thing due to a worn stator (internal part). Replaced it and it starts perfectly now.