Though formal qualifications aren't a must I can assure you from an instructors point its quite obvious which students have brushed up on maths & physics.
All above replies valid, regarding physics it would be useful to know the gas laws (Charles & Boyle) also some basic DC & AC electrics (Faraday and EMF).
All these should be covered during a course, but any advanced reading is always a bonus and gives you more breathing space.
The most important thing in the maths is being able to work out a gross error check BEFORE you hit the calculator. Some students are too keen just to press buttons and come up with an answer and the calculator can't be wrong!
When you move on to the flying you won't have time to play with calculators so mental sums and gross error checks are going to be vital.