Some students can't access the skills I assign while other can. Why?
Have the students that aren't receiving the assignment, completed the Skills already? If not, I read somewhere that if students have completed the first level of said Skill, it is needed not be assigned. That was from a post like this from a few months ago.
I am having the exact same problem. I have no idea. In the past Duolingo would "unlock" the lessons so the students could all get to the lesson, but I have had several bring me their computers, and they have to get through a checkpoint in able to do the lesson.
.. they have to get through a checkpoint in able to do a lesson.
Please, submit a bug report via