When I had my child care center I used "Mailbox" curriculum and I bought a monthly idea book from a local office supply. I planned my curriculum a year in advance and it was very easy with the books.
For example: February
Colors red, white, and pink
Week 1
Numbers, 5, 6, 7, 8
The human heart, book has booklet that can be colored, cut out, and bound
Listening to their own heart and family members hearts with a stethoscope
There were activities for every day and all tied together very well
Send out notes to parents to have family members mail valentine cards to the kids here at the center
Week 2 Valentines Day
make valentine mailboxes out of book
Kids should start receiving mail at the center, put in their own mailbox
eat red and or pink foods at snack time, have them pick the right colors out of a selection of different things
Use the recipe ideas in the book
Have Valentines Party
Week 3
U S Postal service
Go to post office and tour as much as possible, or UPS or mailboxes etc... somewhere the process mail to some extent.
play the games in the book, sing songs about the pony express,play ponies on stick horses, etc...watch video from library with Aurthur and the Pony Express.
Week 4
February is National Dental Month
Dentist week. Maybe have dental cleaning this week on Friday
Use patternout of book and make giant toothbrush and mouth out of box. Use yarn to floss the "Teeth"
Give the kids new toothbrushes
There are tons of ideas in each and every book. Each month is different and offers many choices. Sometimes I would combine different themes in one week. For example Leprechauns and rainbows, easy fit together.It made the whole year fun and exciting because I knew exactly what I wanted to buy, what foods for snacks, and meals to try, new songs and activities, everything that I needed. They also offer online stuff to go along with the books but I really never had time to add of them.