(Sample link) NASA for middle-school students http://www.nasa.gov/audience/forstudents/5-8/features/index.html
(Sample link) National Geographic for Kids http://www.nationalgeographic.com/kids/
Plants http://www.mcwdn.org/Plants/PlantsMain.html
Learn how to make things http://www.funology.com
Electricity Game http/www.andythelwell.com/blobz
Musical Plates( Plot today's Earthquakes) http//www.k12science.org/curriculum/musicalplates3/en/studentactivity1.shtml
Inquiry in Physical Science http/www.inquiryinaction.org/ScienceBackground.html