The science classes I took in school never got much beyond the ones called simply "science." I did take a biology course, but the only reason I passed it was because I sat next to the girl who the teacher had a non-sexual crush on.
I suffer from a difficulty that a lot of people probably suffer from: I can't just MEMORIZE a fact, I need to know how the fact WORKS. This caused problems in highschool science, where they want to just teach you about "refraction" without explaining what light is, how visual perception works, and the exact atomic structure of the material the light is bouncing off of.
For the last ten years I've been catching up, learning (and UNDERSTANDING) all those things that previously only registered long enough for me to write the exams. And while I know I'll NEVER understand the math behind atomic-level physics, I'm finding that if I approach it in enough different ways -- and take lots of rests between each information binge -- I can begin to know what's going on.
This latest binge was inspired by Simon Singh's "The Big Bang" which -- besides reinforcing my understanding of general and special relativity -- reawakened my desire to understand SOMETHING about chemistry. Without understanding WHY the periodic table is laid out in such a quirky way, I can't begin to absorb the information IN the table.
Fortunately, this prompted me to go back and re-read "The Periodic Kingdom" by P. W. Atkins. The book presents the periodic table as though it were a physical landmass. The reader "walks" through the kingdom, discovering similarities between adjacent regions (what happens if you pour water on cesium?) and differences between the sections of the land -- atomic weight and density, ionization energies, radioactivity, etc.
Under the guise of describing the kingdom's "government and institutions," Atkins eases you into what the elements are MADE of, how their electrons form into different types of "shells," and -- ultimately -- why the periodic table IS laid out in such a quirky way.
This second time around I'm finding myself understanding it all COMPLETELY. I've had an actual epiphany. This is the first time I've gotten a "feel" for chemical elements, which is a pretty significant thing for me; it means I can hopefully take it further with "The God Particle" (Leon Lederman) and "Hydrogen" (John S. Rigden), which I just picked up on my way home.
What's my point? I have two: if you don't understand a concept and you really WANT to, try reading two (or preferably three) books about the subject...by walking repeatedly on the same ground -- but from different directions -- you can get a much fuller understanding of things than you would if you just memorized the facts. Secondly, if you really want to get a starter in chemistry, pick up "The Periodic Kingdom." I guarantee it will get you started.