Agree with zmm about motivation, support and encouragement.
I personally don't enourage tuition, however enrichment class like drama, arts, music, I have no objection. When enounter difficulties, I prefer my child to seek teacher's or classmates' help or source for answers through internet, books, forum. I always want my child to find answer the difficult way, then she would appreciate the answer better and remember the process well.
Active learning approach is very important. Nobody teach a child how to play computer games, how to msn, how to blog, but naturally its their interest and they would pick up very easily. This should apply to study. Just to share my thoughts .... no offence .....