Some university officials said they supported the protests as long as they remained peaceful.
"My heart and my support are with everybody and anybody who wants to stand up for public education," University of California President Mark Yudof said in a statement. "Public education drives a society's ability to progress and to prosper."
In Wisconsin, more than 25,000 students have been put on a waiting list after the state's premier financial aid program ran out of money because of increased demand.
At the University of Illinois, about 200 professors, instructors and graduate faculty marched through campus carrying signs that read "Furlough Legislators" — a reference to recent furloughs and 4% pay cuts imposed on thousands of university employees.
The state is $487 million behind on payments to the University of Illinois. State government has a budget deficit of $13 billion.
In Olympia, Wash., a group of about 75 protesters arrived at the Capitol bearing a faux coffin emblazoned with the slogan "R.I.P. Education."
They were later ejected from the state Senate gallery after interrupting a debate with a protest song that followed the tune of "Amazing Grace."
"I once could eat, but now I find, I can't afford the food," they sang.
Several Democratic senators applauded the performance, as security guards escorted the protesters from the building.
In Northern California, rowdy protesters blocked major gates at two universities and smashed the windows of a car.
Protesters at the University of California, Santa Cruz surrounded the car while its uninjured driver was inside. Earlier, demonstrators blocked campus gates.
University provost David Kliger said there were reports of protesters carrying clubs and knives, but Santa Cruz police Capt. Steve Clark could not confirm those reports. No arrests had been made.
An advisory posted on the school Web site urged people to avoid the campus because of safety concerns.