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.
I have created a six video YouTube playlist Geometric Algebra, about 72 minutes in all, taken from the book. Some knowledge of linear algebra is a prerequisite for the videos, but no knowledge of geometric algebra is assumed. The book assumes no previous knowledge of linear algebra.