Fraction Flower Sorts would be super simple. Just cut out several petals from different colors of cardstock paper and yellow centers. You can make the sorts so many different things! In the picture, I made equivalent fraction sorts, but you could do fraction families, different ways to show time, shapes (think "rectangle" on the circle piece and on the petals - 2 pair parallel sides, 4 right angles, a drawing of a rectangle, etc.) If you don't have time to make your own, these Fraction Flowers are available by clicking here.
Here's another tip for some of these activities. Make them self-checking by putting matching symbols, stickers or answers on back. Even though in the picture I wrote the answers on the back after covering it with a piece of blue painters tape, I highly recommend just using matching stickers. For one set of matching pieces, use the same color or style of sticker. Then for another matching set, use a different type of sticker.
If you are looking for some already prepped spring math centers, you can check out the test prep spring math centers I prepared for my classroom. They are available on TpT. Here is a sneak peak of the variety of topics in the pack!