Finish all assignments
I have a couple of students who have finished all the skills for Spanish. Is there a way to add more skills to the system? They have also bought all the extra ones offered to them. Thanks!!
I agree with KenBookmye.
Start the 'reverse tree', the course 'English for Spanish speakers'. In this course your students will have to translate much more from English to Spanish. Especially in the web version of Duolingo.
And it gives them the opportunity to read and write in the Spanish discussions. This is really a great feature of Duolingo.
Here is the link to the official Duolingo Help Center for 'How do I switch my Duolingo course language?
And here is a link to a discussion with a good advice given by hughcparker: https://www.duolingo.com/comment/21155333
They can't add more skills - once the course is finished, it's finished. After finishing the tree, get them to keep the tree gold for a while, to let Duolingo's spaced repetition algorithms help them to revise the stuff they've learned.
While keeping the tree gold, though, it's time for them to move on to new resources - Duolingo is for the first stage of learning a language.