If your family has financial issues, considering you’re young, you could prep for the new SAT or the ACT + take as many AP exams as you can and attend a university with a full tuition or even a full ride scholarship. Howard (in DC) has a full ride that even cover the cost of books if you score high enough, and you’ll get to learn about African American culture and history which I find a bonus in 21st century America (where diversity is valued and non-European cultures need to be represented at all levels). UAlabama TUscaloosa is famous in this forum for its automatic generous, full-tuition scholarship.
(If you spoke French I could direct you to public French lycees with boarding schools).
Have you taken the SAT or the ACT or the PSAT or PLAN?
Do you have any idea how much your parents can afford for housing, food, and books?
Look for Gymnasia in a rural area - many students will live at school during the week and perhaps you can have a boarding family.
Are you currently in Germany for Studienkolleg?
Sciences Po is a top college in France with a program in English and intensive French. IF you’re admitted to the Columbia program after 2 years in France you move to NYC and you get a French and a US degree.
What does your mom say?
Is your family currently in Germany and if not, where do you live?
The AFS program in the US is a high school program. In the past, some students who enrolled had already completed high school in their own countries. I do not know if that policy has changed. However, your age is an appropriate one for the program, and even if you have graduated from high school elsewhere, the program could be a good social fit for you.
Î agree about AFS. There’s also ASSE and NACEL.
If you want to live and work in the US, getting a degree from a German university is a bad idea.
If you want to live and work anywhere in the world except for Germany and Austria, getting a law degree from a German university is a spectacularly bad idea. And there is no such thing as an international law degree - all law degrees qualify you to work in a specific jurisdiction, and international law will be taught as an elective, or maybe a specialized graduate program. If you are very highly qualified, with a top 5 % degree and exceptional language skills, corporate law firms with an office in both the US and Germany might hire you to work in the US. But if you actually prefer to work in the public sector in the US, steer clear of non US law degrees, period.
A business or economics degree might be somewhat more portable, but frankly, the only degrees from Germany I’d think have value in the US would be degrees in engineering and possibly the physical sciences (and music, but that’s probably not an option).
Nor do I imagine that you will get either a visa or a place at university as an unaccompanied 15 year old. German universities do accept minors, but the idea is that either the kid is 17 and will turn 18 late in huge year, or that the kid, radically accelerated due to being profoundly gifted, will live at home and commute, or at least live close to their families. It does bear repeating: German universities are commuter universities who cater to adults, and there will be no support system as you know it.
Spending a year at a Studienkolleg and starting at at least 17 might actually be the best option, because there will be smaller classes and hopefully a strong international community of students looking out for one another but the choice isn’t up to you: you apply to the university and the university decides whether you get to start in regular classes or at the Studienkolleg.
In order to study at a gymnasium, you do not need citizenship (loads of immigrants at gymnasium) but you do need to establish a legal place of residence. Again, I cannot imagine you would be able to get a visa as an unaccompanied 15 year old to set up a place on your own. If the main goal is to learn perfect German and understand German culture best bet would be an international exchange program, as PPs have suggested. After a year, you may see more clearly where you want to be or you can accomplish that, eg remain in Germany or apply for scholarships at US colleges.
Boarding schools are expensive. Period. If your father wants you in a German boarding school, he has to come up with the money.
I would look into United World Colleges, there is one in Freiburg. Not sure whether you are eligible having a secondary school degree, but they give full ride scholarships and you’d come out with an IB. UWC students have scholarship options for tertiary degrees in the US as well.
Law in Germany is totally different from in the US. In is not based on English common law, but it closer to Napoleonic and Roman law. It probably is also significantly different from law elsewhere in continental Europe also. If you get a law degree in England or Canada, you can probably pass the bar exam with some study in the few states that allow a foreign law degree. The law also varies from state to state and Louisiana is very different, as it is closer to French law than English common law.
My father knew someone who was Jewish and had been a lawyer in Vienna. He was in his 40s when he came to the US. He did not practice law in the US, as it would require probably 3 years of law school again. Instead, he got another job that used his knowledge of business and research and negotiation skills.