Should a professor require students to attend classes well past their listed times?
The usual advice is to first try to work things out with the professor. In more extreme cases, if you can't work it out with the professor, you should move to their immediate supervisor, which is often the department head / department chair.  

Different universities have different cultures about professors extending class. At some, it would be viewed as normal, while at others it is unheard of. So you should make sure to take into account the culture of your school in that regard.

With that being said, I think you indicated the professor is adding an extra 150-240 minutes per week (if I read the question correctly). That seems unreasonable, in my opinion, and I do think it is reasonable for you to ask for a better way of handling the presentations.  Even if the professor mentioned this in the first week, it is such a large amount to time that it could seem like an unfair imposition. 

One option would be to simply email the department chair. Be very brief in your statement: one or two sentences on what is happening, and one or two more explaining how you have tried to discuss the situation with the professor. Phrasing the email to the chair as a request for advice is one polite way to raise a concern: "Here is what the professor is doing, do you have any advice for handling the situation?" That gives the chair a lot of flexibility in responding.