With my young kids, the months determine which books I bring out according to season. Fall is topics like Johnny Appleseed, apples, autumn books, pilgrims, etc. Winter is hibernation books, Christmas stories, snow books, etc. Spring months are topics like plants, flowers, butterflies, etc. Summer is a little less but I am sure you get the idea. 🙂
I like to buy each child their own little calendar to mark off the days. They recite the date and we talk about how to spell the month and special observances or holidays throughout the month. It’s very easy and fun!
By the way, I store the aforementioned seasonal books in a special box and change out the books each month. The current books being used are kept in a convenient basket on the kitchen table where the kids can browse during meals.
HTH!