We've finished the first unit, which was on real numbers. Unit two focuses on complex numbers and their operations, and solving basic quadratics with complex solutions.
I went through the main ideas with them about what imaginary numbers are, how the imaginary number line works, and multiplying imaginary numbers. I used the "multiplying by i = 90 degree rotation" idea that I wrote about before, and with the use of Keynote animations, it was even more effective. I really suggest using this method to teach about powers of i.
Here are the files:
Lesson 1 (Intro to Complex Numbers)
Lesson 1 Keynote