We moved to Mentor in October and I have extensively looked into possible preschools for my son, who will be 3 in August. There is an accredited Montessori school in Concord Township, called Hershey. There are some other Montessori schools in Kirtland, Willowick and Willoughby. And just so you know, a brand-new Waldorf school will open it's doors in the Heights this coming fall.
All this said, they are all pricey, so we will be homeschooling after all.