I'm so glad I recently stumbled across www.daybydaysc.org. It has simple lesson plans for preschool teachers and parents for every day of the year. I also think this site would be perfect to share with those preschool parents who ask what they can be doing at home with their children. The lesson plans include songs, videos, e-books, science projects, unit studies, and much more.
You can also download additional monthly ideas HERE.