"Leading Cadet is the second highest cadet rate, and to become one requires several things. You must have 30 points, hold a pulling coxswain certificate, be at least fifteen years old, and will need your CO's recommendation (you may be required to attend a leadership cours).
Then you can take your LC's board, which is a (normally) weekend long series of tests and interviews, to assess your suitability. If you pass you become a senior cadet, and get a badge of rank depicting a fouled anchor for your best uniform, epaulettes, and also, males, for your white fronts (worn under best uniform). As a LC you will probably teach other cadets a lot of the time, and may be in charge of a section of the unit."
I googled the exact same as you did (without the quotes as putting quotes round things means it will search for that exact phrase) and then click pages from the UK (the top results otherwise were all to do with hong kong). the top answer was a doc that contained the above.
http://www.google.co....eskOjXDA&ved=0CAcQpwU