Happy Passover or Pesach!!
Passover commemorates the freedom of the Jewish people from bondage in Egypt. The term Passover refers to the Angel of Death passing over the Jewish homes marked with lamb's blood and killing only the first born sons of the Egyptians, including the Pharoah's son. The death of his son was essentially the last straw in a series of misfortunes and the Pharoah let the Jewish people go free.
People prepare for Passover by cleaning their homes and removing all leavened foods. Leavened foods include things like yeast bread and cakes. You can practice removing the leaven with this online game.
Families celebrate Passover at a Seder which is a religious ceremony/dinner. They eat special foods and read a Haggadah. For fun, check out Uncle Eli's Haggadah.
The above graphic is a representation of a vegetarian Seder plate. On it is a beet (instead of a shankbone), an apple, nut, and spice mixture, bitter lettuce, parsley dipped in salt water, a roasted egg, and some horseradish. Each item represents, among other things, the bitterness, tears and sacrifices of the Jews in bondage.
Torah Tots Pesach
Passover Activity Pages
Find The Chametz
Passover Books For Kids
Penny and the Four Questions by Nancy E. Krulik
Make A Wish, Molly by Barbara Cohen
All-Of-A-Kind Family by Sydney Taylor
(This book has a wonderful chapter about Passover. I loved Sydney Taylor's books when I was growing up, but I think they are only available at the library these days.)