Sonlight Curriculum
company
is a Christian business that has
been around for about 20 years. Their approach is a little different
and seems to fit better with some families. They actually have 2
different Christian preschool curriculum programs – a 3/4 year old
program and a 4/5 year old program.
The Sonlight curriculum is literature-based. Even starting with the preschool programs, you will receive a package of "trade" books (basically picture books), along with an Instructor's Guide full of lesson plans.
The younger preschool package is called "Fiction,
Fairy Tales, and Fun for Little Learners." I would say it is a great
introduction to the idea of school for preschoolers. You receive a
collection of books and Parent's Companion offering activity ideas for
each story. There are no workbooks or lesson plans for this age.
The older preschool package, "Explore God’s World," goes a little further and would fit more with what most parents consider "preschool" – that is, preparing a child for kindergarten. There are 31 books, along with lesson plans that extend the learning for each one.
Subjects that are taught using the books are language arts, world cultures, science, Bible, art, and "Readiness Skills" – skills that develop distinct motor, visual, auditory, and comprehension skills. Some parents add on a handwriting and a math program to supplement the package.
One thing that I love about Sonlight' preschool curriculum program is that it incorporates so many classic picture books. There are lots of great lessons and discussions that you can have with your child based on your reading together.

Another great aspect is that, as the Sonlight website puts it, "Our flexible daily plans make it easy for you to customize your schedule to fit your family's needs and focus on the joy of teaching your children."
Sonlight's curriculum is Christian. As Sonlight says, "While we believe that academics are and ought to be based on and intentionally related to Scripture, and while we seek to act on that belief, we do not believe that everything we read must be accompanied by a reference to or quotation from Scripture."
The price is somewhat less expensive than Alpha Omega, which may make a difference for some families.
I would recommend Sonlight curriculum as they are a great option for many Christian homeschooling families.