For specific topic search I use few sites which I suggest other educators and parents to use for their search as it can save your time.
* 'The Educator's Reference Desk' is created for education community. It offers 2,000 and more lesson plans, more than 3,000 links to online education information, and 200 plus question archive responses.
* Another site is 'eduhound' which is a highly specialized educational directory with FREE categorized resources, lesson plans, clipart, and site sets for educators, teachers, students, and families.
* More than 1600 federal teaching and learning resources organized by subject: art, history, language arts, math, science, and others -- from FREE, the website that makes federal teaching and learning resources easy to find.
- Link: http://free.ed.gov/
* 'EdHelper.com' offer stuff covering topics liks 'Math, Reading Comprehension, Themes, Lesson Plans, and Worksheets.'
* 'Shambles'
' You can use 'Similar Site' to find more relevant results.