Here is a link to
Part I (of VI), for the preterite.
Here is a link to
Part I (of II), for the imperfect.
Both of these links take you to the same unit (visible to the left when you navigate there). You can start with the very first lesson in that unit.
Here is a
place that looks fun (games and challenges to the left).
I think you already know most of the material taught, but it never hurts to review.
