From the Publisher:

When our Astronomy, 2nd edition, was first released, we produced an exclusive kit that had a bonus Activity Guide along with the materials to do all of the regular and the bonus activities. We have since run out of stock and do not plan to reproduce it. Due to popular requests, we have made the bonus homeschool astronomy activity guide available separately.

There are other companies who sell various kits to go along with our courses. They are really just a convenience item as the activities use common household items or things you should be able to purchase at a local store. If you want to purchase a kit, as long as you choose a 2nd edition kit, it will be compatible with the 2nd edition course.

Please note that our astronomy course is complete without the bonus activities and is n longer referenced in the textbook nor the notebooking journals.