A rather comprehensive resource for Physics Content, Physics Classroom provides supplemental instruction and easy visualization of concepts
Community Review for The Physics Classroom
Use the text and tutorials as supplemental instruction or provide more in depth instruction. Not all topics are supplemental to an AP or IB level. Some core concepts are missing. (Fluids, Thermodynamics). Demos can help students visualize the concepts. Take into consideration audience maturity, you may need to re-direct if they are not engaged or add more info to a given activity or demo. Always put the lesson in context of your class first. CP Physics may find this more useful then AP/IB. May go as far as M-level in SAMR hierarchy in terms of how you can introduce lab concepts or perform labs virtually.
How I Use It
This is site is used for supplemental instruction, as well as providing demos for equipment I don't have. The demos work when I don't have extra time or equipment. The supplemental text and practice questions allow students to clarify and learn the info that may be missing, or if they were absent they can make up the general concepts on this site.