Turns out the bug was caused by an infinite loop in the Detail View Controller. Apparently, if you put a alert inside of a do-while loop, it won't actually display the alert and take in user input before checking the loop condition. So, it keeps looping but never launches the alert.

BUT, my device for passing back new students to the view controller to be added to the class roster array worked flawlessly. You know what that means? It mean's I'M DONE!!!!