This textbook for the first undergraduate linear algebra course presents a unified treatment of linear algebra and geometric algebra, while covering a majority of the usual linear algebra topics. The link is to the book's web page.
December 21, 2016. Fourth printing, corrected and slightly revised. There is a new chapter on the conformal model.
I have created a six video YouTube playlist Geometric Algebra, about 72 minutes in all, taken from the book. Unlike the book, some knowledge of linear algebra is a prerequisite for the videos. The book assumes no previous knowledge of linear algebra.