How to drop tables shown as Missing in Schema Report During development/testing after using Backup and Migrate Restore in conjuction with Schema, Schema will show Extra tables no longer referenced in the database, used by modulesetc, and no longer required.  

How can these tables be removed with a module or within drupal with api/php? Can a form be created to specify select tables to drop?
Check out the db_drop_table function.

You could use it on the mysite.com/devel/php page which runs arbitrary php for you, but be ultra careful with it and always have backups, because if you get it wrong you could completely kill your site.