I am in my 7th year of home schooling, and I also ran my own preschool for 2 years. For my 3-yr class, which included my youngest child, I used Funshine Express Fireflies. It is a wonderful program, and the kids all loved it. It is for ages 2-5. Check it out at www.funshineexpress.com. You can order a sample kit to check out.
You can buy either the monthly kits, which I did, or just the monthly guide and teacher materials. I liked the kits, because everything came ready to go, all the worksheets, craft supplies, all set! But, I had several kids to work with and was home schooling my 2 boys also - so I needed the help! Having only 2, you could put the crafts together yourself and save a ton of money.
The parents of my preschool students loved the program too.
Most of all, have fun! The "circle time", when we taught the curriculum, was a small part of our class day. We sang songs, played games, read books, etc. and had a blast.
Good luck!