Antonyms? Synonyms? Homonyms? Also, idioms? Analogies? What doesn't belong in this group and why? (WH) questions? If you don't have picture cards for these, Google it, with 'pictures' or 'worksheets' after the category.
Also, classroom vocabulary, taken from their textbooks, but YOU work on having them identify a word when you say a definition (receptive) and then they provide a definition and use the word in a sentence (both oral expression).
Ask their LD teachers what language or vocab areas they feel the students need?