newmom, you're right-- those are really insightful and meaningful questions, and your advice is very good as well. If I were the one driving this bus... I'd have her do German as a first foreign language... because I have a reasonable background in German (well, Dutch, actually, but I have formal instruction and actual usage of German as well).
Failing that, my own inclination is that the following things are true of the options available locally:
German-- easy to continue since it's common enough in foreign language programs, there is enough crossover with Anglo-Saxon languages that it's reasonably easy for English speakers to start with, we have a neighbor who is fluent (and already a friend of my DD's), and I can help.
Latin-- LOTS of resources and lots of people who've taken enough of it (my DH included) that she'd have plenty of help, it is a "foundational" foreign language that unlocks French, Spanish, Italian, and Portugese. She might later find this most useful since her interests are in jurisprudence, and therefore a passing familiarity with Latin is useful to say the least.
Spanish-- lots of opportunity to practice in the real world, as we live in a very diverse community whose primary second language is Spanish. Both parents would be interested in side-by-side learning there.
Czech-- the neighbor who is fluent in German is a native Czech speaker.
French-- I can (bumblingly) fight my way through most French up to about 8th-10th grade reading level. Speaking is another matter, but at least I have passing familiarity with grammar and verb conjugations, gender of nouns, etc. Years of high school French and I can open a conversation with "Comment �a va?" Too bad all I can do after that is pick up about every third word and look puzzled. LOL.
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Those are MY preferences. However, with an 11yo strong-willed EG/PG child, much of that becomes irrelevant. SHE wants to learn Greek so that she can READ in Greek.
Okay, so bottom line is that this is why I studied German in college-- it was pragmatic given my major. It has actually come in quite handy over the years since there is still literature that is published en Deutsch and NOT in English, too. Being able to accurately translate a materials and methods section, as well as figure legends in conclusions sections has turned out to be quite a boon.
So I have to respect that my daughter's reasons might well be fine for her. Greek and Latin are probably never wasted time no matter who you are or what you plan to do with yourself.
The other factor that I'm taking into consideration here is that this is a way of granting autonomy that my daughter is really craving educationally. In other words, my suggestions have to be just that-- suggestions. If I make them 'commands' or even 'coercive' seeming to her, she will lose all interest in a hurry. It can't be MY agenda, in other words, but she's also sensitive to criticism of her ideas. So if her dad and I logically point out why what she wants to do here is fatally flawed or a waste of her time, she may well back off-- but that doesn't mean that she'll take direction from us. She'll just give it up entirely. I'd rather that she did something her way than nothing at all.
We also have some real limitations financially, so "hiring" a tutor isn't really an option, unless she's willing to give up something ELSE to pay for it, or unless we can get a college student to do it for almost nothing.
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Is the RS program Koine? Or another dialect?
At this point, I really don't know how intense DD's interest is likely to remain. She can blow hot and cold with things, so it's possible that she may decide that Greek is not her thing if she isn't making as much progress as rapidly enough as she'd like.
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MM, thanks for the tip on the new study group starting. Is this listed on the website somewhere, or only via listserv? Ie- how would she sign up? (Sorry if that is self-evident, but it didn't seem obvious to me with a cursory look over there.)
