When I introduce new grammar, I sometimes have students make manipulatives. We make an "endings box" early in first year, when we're using Nominative and Accusative only. Later, when I introduce all the personal endings for verbs, I help them create a "present" which will conjugate and translate a sample verb for them. I have others I have used with other tenses, but all of them are the same basic idea in different shapes (a sheep for Imperfect, a crystal ball for Future, and "100" for perfect).
I have stopped doing these manipulatives as much because I felt like my students were relying too much on them, and were not actually learning how to do it themselves. I'm considering having them create one this week for the passive verb endings, emphasizing that when they use it, they are BEING shown how to do it, not doing it themselves (passive vs. active).
I also have some wooden blocks on which I have written some vocabulary words (each face of the block has a different form), and students use them to "build" sentences. It's great because I can tell based on block shape and color whether the words are in the right order, then when I approach their group, I can correct the form by rotating the block as needed. They love this game so I use it every year, but it only lasts a little while because there are only so many blocks! (And they're not cheap!)
Does anyone else use manipulatives, and if so, what?