Well, DS (3 1/2) attends a RE school. (See my post below looking for another one since we are moving.) Ours is a public school and DS attends as a special education student--it's an inclusion classroom.
It's a great fit for DS. The emphasis on community and communication have really clicked for him. I think the teachers do a nice amount of guiding the students to learn and leaving the students to discover. There is not a huge emphasis on learning letters, etc. Although they do some of that stuff. They spend about an hour outside each day (DS attends mornings only, but other students do attend all day). They spend some time with books, songs, etc in small group. And they spend time in the art area, block area, house area, etc.
Hope that helps!