Here are video of lectures you can use for review (or occasionally in class).
In Class Lectures - Spring 2010
Introduction to Ohm's Law - Quick introduction to Ohm's Law and the relationship between voltage, current, and resistance (1/27/10)
Introduction to Arduino 1 - Variable types, binary numbers, basic Sketch structure. (1/29/10)
Introduction to Arduino 2 - Using LEDs with Arduino, why do we need resistors, how do we use them backwards? Intro to Charlie Plexing. (2/2/10)