Looking for fun seasonal science experiments? Check out Education World's Easter themed science experiments. There are a range of ideas appropriate for all grade levels. Teach your students about air pressure with the egg in the bottle trick. Teach them about solutions and osmosis using eggs and a few simple ingredients. It's all here.
One of the most memorable science experiments my chemistry teacher did my senior year of high school was to blow up a peep in a vacuum. This short You Tube video will show you how. Save your students from the sugar high and show them something to do with peeps that is much more fun than eating them.
Want to give the students something to take home? Want to bring a bit of culture into your Spanish class at Easter time? Make cascarones or confetti eggs. This is a Mexican tradition. I have done this with young kids and they think it is tons of fun to empty, clean, decorate and fill the eggs with confetti. And that is just the fun they have before they go around breaking them over each other's heads!!
A German (well, not just German, but I learned it from a German) tradition is creating blown eggs. Again, this is a fun take home project. The difference is that this take home project is actually meant to be preserved. Create an Easter tree in the classroom and then let the kids take their eggs home right before Easter as gifts for parents and grandparents. I've done this with young kid as well, and it was also a big hit.
I hope this provides you with a few fun ideas for students of any age. Happy Spring! It may not feel like it yet, but it is right around the corner!