I disagree that SEO should be taught in colleges, or that there should be certifications for it.
SEO requires constant learning, testing, and adjusting. By the time you finish a 4 year degree, the tactics and guidelines you learned in year 1 may be completely obsolete.
Each SEO is different. Everyone has their own opinions and techniques. That is the nature of the industry, and why it's so interesting. There is no one right answer, there are many different ways to get to the top, and even more that make it harder to get there.
SEOs also use an ever-changing set of tools, which also is adapting and changing with the industry. The tools you learned while at University are probably outdated or obsolete by the time you graduate.
I personally think that a degree in Marketing or Communications will set you up for a great start in the SEO field, but the majority of the leg work to learn industry standards, tools, techniques, etc., should not be taught in school.