Running a school chess championship

I spent today helping run the Amaroo School Chess Championship. It was open to students from 4th grade up to Year 10 (it is a K-10 School) and attracted around 90 players. The bulk of players were in the younger age bracket but it was still nice to get 20+ players from the High School students.
While there were enough sets to cope with the number of players, we had to be inventive with the clocks. The system used was to start the round without clocks and after 20 minutes, put clocks on any games still going. The time left to complete the game was 5m each, meaning that each round lasted around 30 minutes. There were no problems with this method, and at most we needed 5 clocks to finish any particular round. Most players were happy to move reasonably quickly, and I only had 1 complaint of a player 'sitting' on their position.
We only had time for 6 rounds, and it was a close run thing to see if we could find a single winner. The number of perfect scores went 40->20->10->5->2 after each round. The loss by one of the players on 4/4 against someone on 3/4 avoided the need for a later playoff. However there was still a huge tie for second place (9 players on 5/6), with the minor awards being distributed by tie-break.
This years winner was Vivian Lam, the second year in a row that the tournament has been won by a female player (Jennifer Ton won last year). This is not that much of a surprise as Amaroo does a lot to encourage girls chess, as well as the fact that around half the field were female.