Mary Poppins London Theatre Tickets

Best ways to get inexpensive theatre tickets in London?

I’m from the US, and I have a student ID. I’ll be in London for the first two weeks of April. I mostly like musicals, so show recommendations are welcome too! (already have tix to Billy Elliot and Mary Poppins)
The person who actually gives the best answer will get the vote. That is all.

One way of getting inexpensive tickets to West End is to go to Leicester Square. There are a number of booths offering half price tickets to several productions. Take note, however, that half price deals are usually only available for the less popular shows, and that for popular productions (like the Phantom of the Opera) or shows that have recently opened, you may not be able to get half price tickets. Half price ticket booths normally take a small commission for each ticket purchased.

Another possibility is to go to the Theatre itself about an hour before the show and hope for return tickets which become available when people cancel their bookings. These tickets are usually offered at a discount.

Mary Poppins – Melbourne