I am a sophomore in high school, and am becoming very interested in physics. It started when I was young and did a report on Albert Einstein, but is just now blossoming. I'm intrigued by nearly all areas of physics, and have just now begun to further my knowledge. I've read Beyond Einstein and most of Hyperspace (I'm still reading it), both by Machio Kaku. The problem with some of the information in Hyperspace is that it is either beneath me and prior knowledge, or too complex (mostly the math when it gets into string theory, like symmetries). The reason for this post is to see if any of you in the science community might have some good intermediate level books that can teach the math and concepts of physics. I'm not looking for a text book, but more books like those of Machio Kaku would be nice. Ones that explain the math in relation to a physical occurrence is good because I learn very quickly that way. I'm a somewhat advanced math student, and am good at teaching myself, and would like to gain a greater understanding of physics in general, though I’m particularly fond of relativity and string theory in terms of what I would like a greater understanding of. So if you know of a good book that fits this criteria, I would love for you to share it with me. Thanks in advance!