Spack,
One thing that might help is to develop the WRITING skills of your kids, one language at a time (if only one language), and preferably in your own native tongue (i.e. English) so that you can help them along the way, though some parents may choose to hire tutors for the second language.
In my case, like many other second-generation Chinese-Americans, I grew up with parents who were trying to learn English at the same time that I was learning how to speak.
My parents moved from Taiwan to the U.S. when they were in their early 20s and barely spoke English at that time. Though they both have actively endeavored to master the English language ever since and are pretty GOOD at it by any measure (my mom till this day keeps an English-Chinese dictionary next to her computer and a notepad where she writes down words/phrases she is not familiar with and then harasses me on email for examples on how to use them correctly, etc.), I didn’t grow up learning lots of “big” words or intelligent thought processes in English, in spite of television, radio, etc.
At the same time, they didn’t see the need for my brother and I to learn Chinese to the extent that they would force us to do so, since we were living in the South, there weren’t a lot of Chinese people (never mind Chinese classes), and they didn’t see themselves returning to Taiwan for a long time.
The net effect is that my English vocabulary, use of sentence structure, and overall thought composition, was SO-SO compared to my “American” friends (and my listening comprehension skills in Mandarin at the bare minimum).
Whenever I SPOKE in what was supposed to be MY native language, I would find myself stumbling for the right word or pausing altogether, stuttering just as my mom would when she tried to communicate a thought to me and my brother in English (her third language, her first being Shangdonese). I hated it when that happened, and at times I would feel insecure about myself because I could never communicate a thought as effortlessly as the rest of the kids, and yet I didn’t understand why, much less how to address it.
But then I started writing, first in junior high school because our English teacher made us keep a journal, which at first I thought was stupid. But that experience introduced me to the world of journaling, and I’ve kept one journal per year ever since then (pretty much).
heychristine.com/about/sitefaq.html#journals
Even in my online journals which I started in 2000, I can feel/see the improvement in my writing abilities over the years, as it forces me to think about that “best” word to use, to refer to the dictionary more often than if I were just reading books, etc.
More importantly, being able to WRITE better enabled me to SPEAK more coherently, because the effort of thinking about how to present something in writing and then rereading it outloud to myself, to double check on my composition before I published it, reinforced my English speaking abilities.
Till this day my friends laugh at me because I often use English words/phrases inappropriately without knowing it, but I do appreciate that both my English writing and speaking abilities have improved greatly over the years, and thus, my confidence, not to mention the effect it’s had on my ability to run ORIENTED. I have to communicate (write and speak!) to a LOT of people every day… to think that I used to stutter and not know how to present my thoughts clearly… =)
How the development of my English skills ties back into the development of my Chinese skills is this:
I will be the first to admit that my Chinese is NOT TOO GOOD, mostly because foreign languages isn’t something that comes easily to me (for another discussion), but now that I have a solid grasp of the English language, I am in a better position to apply those skills AS I am learning Chinese, even though Chinese entails a different set of language rules, sentence structure, etc.
As you mentioned in your first posting, I too have a lot of friends who were born in Taiwan and grew up in the States, and who speak both languages very, very well, but cannot write well in either (language).
It is not because they didn’t read enough English books or Chinese novels when were younger, as they certainly did a lot of that.
It is because they didn’t develop their writing skills in at least one of those two languages.