Hi John
Well, asking two language teachers about learning vocabulary will get you five opinions, but I'll throw in my thoughts on this. (Based on teaching English as a foreign language)
Firstly, creating your own material is very time consuming but it's probably unavoidable if you are complimenting existing course materials. I try to focus on collocations a lot and use the book activity combined with prepared glossaries. If you add in the Game activity, you can create crosswords and other word games from glossaries and quizzes. Using this combination, you can create a good variety of activities for learners. If you are teaching ELT, then the Vocabulary in Use series from Cambridge University Press offer lots of ideas that can be adapted.
Although the concept is out of favour with some teachers, Moodle is good for drilling vocabulary. With a large database of questions you can create quizzes that evolve (using random questions). My weaker learners particularly like this, as they can practice in private which relieves the peer pressure.
Literal videos also work well. There are stacks of them on YouTube in many languages.
I would also look at introducing audio recording for learners (I use the Poodll plugin). This can check active vocabulary very well.
On a theoretical note, I'd recommend you have a look at Michael Lewis's book, Implementing the Lexical Approach. It's focused on English as a foreign language, but the principles apply to all languages. It adds considerable leverage to vocabulary learning and certainly helped me to get the most out of Moodle's potential.
Hope this helps as a starting point, and I'm sure others here have got more ideas.
All the best
Andy
