Hi @BStutzman ,
Thanks for posting on the Instructure Community!
No, there is not a way to prevent students from removing items from their to-do list. Without this functionality, student's to-do lists can become very cluttered overtime with select items. There might be a way to do this through custom javascript, however that is beyond my knowledge. However, when it comes to just general settings at the account-level, then no, I'm 99% sure this isn't something you can control on Canvas.
All the best!
Noah
