The following links provide additional materials, corrections, etc., for Katherine’s math books and eCourses. Please click on the appropriate book to view the extras available.
Jacob’s Elementary Algebra eCourse Extras
Jacob’s Geometry eCourse Extras
Principles of Mathematics: Book 1 Extras
Principles of Mathematics: Book 2 Extras
I’m a sinner saved by grace through Jesus Christ. I’m also a writer—I’ve been writing ever since I could hold a pen. I… 
