Ah, it's spring again, and college students' fancies are turning to protests even as final exams loom.

In at least four states, echoes of the '60s could be heard as students took aim at proposed budget cuts, tuition increases and union recognition.And at a prestigious college, student protests culminated in getting Coca-Cola products banned.

Thousands of protesting City University of New York students skipped classes Tuesday and marched through lower Manhattan as a deadline approached on a state spending bill that would reduce money for higher education and force a tuition increase. Hours later, Gov. Mario Cuomo vetoed the bill.

At the University of California, Berkeley, teaching and research assistants planned to begin a two-day walkout and picket campus entrances to protest the school's refusal to recognize their union.

Mount Holyoke College administrators in South Hadley, Mass., under pressure from students to boycott Coca-Cola products because of the company's ties to South Africa, announced a monthlong ban of the company's soft drinks.

In New York, about 4,000 students stepped up protests that began last week.

Placard-carrying, chanting students from the university system assembled in front of the World Trade Center, where Cuomo's New York office is located. They blocked traffic for several hours, then paraded past City Hall and to the Wall Street financial district.

"It's not just a matter of this tuition hike. If we let them go, it will be more," said Armando Howard, a 29-year-old physics student. "It will cut out the opportunity for people to rise."

Cuomo had given no indication what his decision would be. But one hour before the midnight deadline, he vetoed it, saying university officials had failed to prove the need for the extra money.

At Berkeley, neither the 3,200-member Association of Graduate Student Employees nor university officials would predict how many assistants would join today's walkout.

"So far, our indications are that this could be more symbolic than a significant disruption," said university spokesman Tom Debley.

The dispute is over the university's view that the assistants' work cannot be considered employment because it is so intertwined with educational experience, said Debley. Assistants receive annual stipends from the university or research institutions averaging about $10,000.