I'm like the OP's brother in that when I started EE, I had already been tinkering with circuits for about 7 years. Obviously, in labs it was a huge help, but it also gave the math and all the abstract concepts learned in class some relationship to the real world.
Having the background means you can glance at a circuit and immediately know that a certain resistor is sized too small, or hearing the high-pitched whine of an inductor means that may be the problem with your regulator. In short: build lots of different stuff, have it blow up in your face, and learn something from the experience.
