Curriki:

Curriki is a wiki-based website that allows teachers to publish lesson plans, activities, or entire unit curriculums to share with the larger teaching community. Lesson plans are broken up by subject, age range, and topic. Applications of this are strightforward in terms of use in lesson planning and sharing ideas for particularly effective activities. Teachers can use the website for inspiration or new ideas, or they can download the specific support materials needed to replicate the published lesson plans in their own classrooms.

curriki.org