Handle case where grade level access is empty
Handle case where grade level access is empty

+ Can't access the "keys" of a split string if the string was nil; grade level access can't be nil, must be []
+ TODO:
  + [ ] Think about a more elegant / less hacky way to do this
  + [ ] Write a system test now that we're on Rails 5.1 and that kind of thing is easier?

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