https://support.duolingo.com/hc/en-us/articles/115000410226-Why-can-t-my-students-skip-skills-for-assignments-

For users familiar with previous iterations of Duolingo's assignment features, you may recall that students had to complete all skills in order, up to and including the assignment you set.
Now when assigning a skill out of order, that skill becomes unlocked for students and they can do it right away.

I don’t think so!