Linda, I think "swottier" should be allowed, not to mention "swotty" and even "swottiest". (Of course it might be a long time before the letters come up again for any of these, especially the 9-letter "swottiest".)
For the benefit of Dean and other North Americans, to swot means to study very hard, and a swot is someone who studies very hard. It's a colloquialism from Britain, but also used in Australia and no doubt other countries. When a person is called a swot it often has a rather negative connotation - "Witherspoon Minor is a beastly swot!", sort of thing.
So "swotty" can mean very studious, or it could be used of a course of study or a school whose students are obliged to study very hard. And "swottier" is the same but more so. An example from someone's blog: "Other kids did: the ones who were geekier and swottier than me. They went to university and got themselves qualifications in abundance."