Sorry for being pedantic, but Royal Icing is *not* just water and powdered sugar... it also contains egg whites.

http://en.wikipedia.org/wiki/Royal_icing

The A-Level isn't the same as a qualification from Cambridge (unless it's a secondary school).

The UK school system is based (mainly) around GCSE's (which are taked during the compulsory years at school) and A-Levels, which are (normally) an 2-year course which are optional - and are used to gain entry into university (if that is your wish).

Of course, the university bit is optional - it's not for everyone... ;)