Our Preschool Program (Fiction, Fairy Tales and Fun for Little Learners) is typically recommended for older 3-year-olds or younger 4-year-olds. It is a loosely structured program with lots of great picture books and developmentally appropriate activities. Our Pre-K Program (Exploring God's World) is typically recommended for older 4-year-olds or younger 5-year-olds. It includes a daily schedule and a series of pre-reading critical thinking workbooks.
You might find it helpful to read this article about teaching preschoolers at http://www.sonlight.com/blog/2013/05/pre-school-just-reading.html.