Every year I do vocabulary building with my students. It is an opportunity to add to their vocabulary and increase their ability to communicate in the target language. I tend to pick a "theme" for my words like a year of rhyming words. If you teach Spanish check out the posts listed in which I share different themes for building your students vocabulary. If you teach another language these posts are still helpful in giving you ideas. These posts give ideas for activities to help your students learn.
Rhyming Words- Rhyming words are especially good for younger kids.
Synonyms and Antonyms -Start with antonyms which tend to be easier, then move on to synonyms.
Idioms might be another great idea for more advanced students. I found this on Teachers pay Teachers and may use it in the future.
Here is my Pinterest board on rhyming words...
If you have any ideas on vocabulary building I would love to hear them!