mfkhung,
Beethoven Piano Competition 2004 is organised by HK Music Association and sponsored by Music Office of LSCD & 樂韻琴行. The competition brochure is available at Music Office of LSCD & 樂韻琴行.
There will be 1st round competition for all participants in Dec 12-14(?) or something. The final will be held a few days later. Participants for Children of or under 12 will be required to play one piece from Czerny 599(No.58-100) & one other Beethoven's easy pieces. We went to see the competition last yr and found that it's more formal than School muisc festival and the average standard of those finalists were indeed quite high.
Hope all these can help you! What's your son's current grading? As advised by Sindy, grade 5 or above standard should be manageable.