Check out this blog post from the Mandel Center for Studies in Jewish Education. They're launching a new website that is a resource for those interested in the question: How can we make day schools excellent places for teachers to learn and grow? It features practical, field-tested resources.
The online toolkit is up and running, and it's free with registration (see here). They're going to be introducing it in a webinar (twice in June and once in August), also free with registration (see here). Go to http://www.teacherlearningproject.com/ for more info.