"Where are you going?"
In my opinion "dokąd" and "gdzie" have different meanings. "Dokąd idziecie?" means in "In what direction are you going?", while "Gdzie idziecie?" means "In what place are you going?"
I'm not 100% sure, so correct me please if I'm wrong.
Well, yes and no. "dokąd" is definitely the best option here, as it refers to direction, and "gdzie" is technically incorrect... but super common. The problem is, that "dokąd" is not taught in this course, so we can only accept it, but we are unable to make it a starred answer.
Is "dokad" more like the Russian куда and "gdzie" like its cognate где? Or is the difference between them a lot more flexible?