Here's a brief overview of the new rules for the Student Visitor Visa (less than 6 months) and the Student Visa/Prior Entry Clearance (greater than 6 months). These rules apply only to students from non-EU countries.
Student Visitor Visa - the Student Visitor Visa is for those that plan a stay of less than 6 months. Under the Student Visitor Visa, a student cannot have paid employment or an internship greater than 2 credit hours, and cannot extend their stay once they have arrived.
Student Visa/Prior Entry Clearance - if you plan to stay in the UK for more than 6 months, if you may extend beyond 6 months, or if you want to work or have an internship greater than 2 credit hours - then you need to apply for a Student Visa/Prior Entry Clearance.
Applying for a Student Visa
You should apply for a Student Visitor Visa, a Student Visa and Prior Entry Clearance before leaving your home country. If you don’t, you risk being turned away at arrival if you do not have all appropriate documents and information.
Generally, to apply for a student visa you will need the following:
Be accepted and enrolled in a recognized full-time degree course, or
A course run during the week involving at least 15 hours of organized daytime study each week, or
A full-time course at an independent fee-paying school
You also have to:
Be able to pay for your course and support yourself and any dependants, and live in the UK without working or needing any help from public funds,
Be able and intend to follow your chosen course, and
Intend to leave the UK when you complete your studies.
Working After Degree Completion
Like the USA, students who complete a degree program in England are allowed to apply for a one year extension to their visa to allow them to gain work experience in the UK, without having to obtain a work permit. Students studying in Scotland are now able to extend their visas and work for two years after completing a degree at a Scottish university, helping to make Scotland a particularly attractive destination for international students.