I've been teaching the needs of living things vocabulary for a few minutes each day over the past week and a half. This gives them lots of exposure to the vocabulary over a chunk of time. We've been practicing "J'ai besoin de..." and 6 words to complete the sentence.
I write "J'ai besoin de..." on the board, and add 1 card at a time as my students tell me them. Then once they're all up there, we go through them again together in French.