Take a moment to look over these sites. There are many different curriculum's out there. Some fit into programs better then others. Many providers make their own curriculum, there are sites here with a lot of information and ideas for themes. Take a little something from these sites, or order from the sites that have them all ready for you. One is not better than the other. You know your set up and your children better then anyone else, pick what works best for your program.
I do not endorse these sites, they are simply put here for you to research and choose for yourself.