This worksheet is designed to give students practice at imaginary number operations, specifically adding, subtracting and multiplying complex numbers. There are scrambled answers at the bottom so students can check their work as they go through this worksheet. This frees you up to go around and tutor students.
The method I use to teach multiplying complex numbers is the area model (or box method). Students seem to understand this better than FOIL. FOIL works ok for multiplying binomials, but the area model helps students visualize what is going on with the multiplication and to organize their work.