With the addition of channels, they have simple segmented some of the content so you have to pay more. The courses channel is really bad. They put a natgeo logo on them so you thing it is a docco, but it is just some phd telling you about their life story for the first 15 minutes then turns into a boring lecture that doesn't really cover much. By means is it worth the extra subscription. And Amazon's annoying system designed it hard for people to cancel a subscription still hasn't changed.