The Woodlands t or t is for the kids who live there, rather than a public event.
Another option is one of the parties at the clubs - any friends who could invite your kids along if you are not members?
Also a number of malls and stores have dress-up hallowe'en events - last year I remember Times bookstores organised something. I think even our local Cold Storage had an event of some sort. Look out for posters when you go shopping.
When we lived in a
condo, residents would ask all who were willing to allow kids to T or T to put a hallowe'en poster (provided by us) on their door so the kids knew it was OK to knock and the residents were well-stocked with treats. Families met for a fancy-dress parade around the pool and brought a plate to share before the kids set off trick or treating. If you live in a condo, you could try to organise something similar - it was very popular with all nationalities.