Since microscope labs begin in Module 1, you should purchase the Biology Microscope and Complete Slide Set prior to starting Exploring Creation with Biology, 3rd Edition. The Biology Dissection Set with Specimens is not needed until Module 13, so we would recommend that you purchase the specimens closer to the time when you will be performing the dissection labs.
Please note: Dissection specimens used within one year will have the best outcomes. The specimens should not be refrigerated or frozen. If the specimens will be stored for more than six months, they should be left in the supplied containers. As long as the original seals are unbroken, the individually vacuum-sealed specimens will remain usable.