Sietske and I often use mini-whiteboards in our lessons. We make sure to hand them out at the start, so they are always readily available for any questions that need a (short!) answer. They are great to use in a think-pair-share activity, and they can even be used in group work.
To make sure all participants in a group (equally?) participate and have a task, you could try this variation:
Find questions with answers that have multiple elements. It could be a phrase of 4 words or a mathematical equation of 4 parts. Instead of having one student write down the complete answer, you could have each student write down a part of the answer. Students hold up the whiteboards in the correct order, and VOILA! Try to think of more ways you could 'stretch' the answer over four boards. Perhaps drawing the stages of a river in Geography, a short timeline for history, or a mini art project. How could you use this in your lesson?