This is a great question!
There are some key differences between our HackEDU Break/Fix lessons and coding exercises:
HackEDU Break/Fix lessons are a dynamic web application. The lessons provide learners the opportunity to break and fix code.
Coding exercises contain a static set of code and are fix only.
One other important note: HackEDU Break/Fix content is available to be added to Quests but Missions remain Coding Exercise only.