Are you talking about the ALEKS test? You take the placement tests as soon as you commit because the sooner you complete it, the sooner you will be scheduled for orientation and that’s when you register for classes. Placement tests are just that…just for placement. You need certain scores to be able to register for certain classes. I only really know about the ALEKS math placement test. I don’t know anything about the chemistry ones. But in general, there really is no studying for them. You know what you know. And you can retake them if you have to. I’d take them ASAP though. Unless we are talking about totally different tests -