We give our kids lots of time to play, play, play with unifex cubes. We sit with them and play, too. Sometimes we help to develop a concept, but other times we just work with the cubes for the sake of playing.
We use unifix cubes for making patterns and addition and subtraction problems. I ask questions like, “What is 3 pink blocks plus 2 yellows equal?”
Then, of course, the kids make towers out of them. Clean up consists of sorting the colors into piles and then building the tower in the proper color.