Kaplan pay can be as low as $13-15/hour in certain areas. You get a predetermined number of prep hours (42?) for teaching the MCAT course for the first time, prorated if you are only teaching some sections. If you are teaching for the second or subsequent times, you get very few prep hours (7?).
First time round, you will probably spend 1-3 hours to prep for each HOUR of class time (not each lesson), especially if you are going to prepare to answer specific questions on the preview/review and homework.