I thought this was pretty neat. Its a website that contains a bunch of lesson plans in science across a bunch of different grade levels. Grade levels go from K through 12 and the topics are wide-ranging
This site has many tutorials and lesson plan starters related to chemistry concepts and topics. There are many great ideas that are explored in this site that can be used in introductory and advanced level chemistry classes
This page gives links to many resources which could be used to enrich physics instruction at the secondary level. Some examples of the resources are an examination of the physics of race cars, roller coasters, and links to some simulations.
This is a site run by the UIUC Department of Physics and their outreach program The Physics Van. Although this is focused more towards the elementary level, it is still a good source for Q and A about physics topics.
This web page is from the UIUC Physics Van and it is a place where people can ask questions about things in their everyday life and get answers from people who are knowledgeable in related scientific fields.
This is an Amazing resource for modeling science topics with simulations! Run by the University of Colorado at Boulder, there are tons of interactive simulations including ones I've used in my classes that are very helpful in visualizing certain topics. The website also has shared activities from teachers across the country including lesson plans, homework, demos, and labs for all grade levels!