More than a million students are expected to be affected by industrial action with lecturers at 64 universities walking out over pensions.
Picket lines are expected at campuses around the country after negotiations broke down, with lecturers saying cuts would leave them £10,000 a year worse off in their retirement.
Senior lecturer Dr Gregory Lane-Serff is one of those striking at Manchester University. He tells me morale is very low.
"Clearly it's very hard for us to take a decision to go on strike. It's not what any of us come into this business for… but we think universities have a lot of money to fund our pensions.
"They've been taking a lot of money in tuition fees but they've been spending less and less on staff."
Many students are furious they're missing tuition that now costs them up to £9250 a year after fees were trebled five years ago.
An estimated 575,000 teaching hours will be lost in the current strike action and some are calling for a refund for missed tuition.
One international student at Manchester University says he's saved hard to afford the £18,000 fee for his one year course and he wants to be compensated for lost teaching.
Another student who studies healthcare says missing lectures will not only impact her exams but her ability to do the job safely on graduation, as every lecture counts.
Universities UK says the pension scheme has a very big deficit of more than £6bn and the cost of future pensions has increased by a third in three years.
In a statement it said: "We can't just ignore this. Without reform, employers and staff would be forced to increase pension contributions to unmanageable levels – an extra £1bn every year."
The University & College Union General Secretary Sally Hunt says they're not pretending there's no issue. "We need to work out a shared way to fund our scheme so that we deal with the pension deficit together," she said.
"It's a healthy scheme and it's not in crisis. We need to find a shared solution, but it takes us to talk and at the moment they're refusing to talk to us."
Many students understand their lecturers' position.
Physics student Bethan Turner is even joining lecturers in Manchester on the picket line and is critical of the rising salaries at management level while cuts are made to teaching staff.
"It's management to blame, it's not the staff," she said.
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"They're refusing to pay pensions, they're refusing to pay staff, what choice do the UCU have?"
The union says how universities react to the strike action this week is key. Any prolonged dispute could significantly impact students as they reach end of year exams.
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