So as soon as it was legally viable - this school year - I put her into an online British high school. Her compulsory ed here in Switzerland is done (they literally give up on your kids at about 15 and push them into the job market)
Now, my kid is bright. REALLY bright. She skipped the first grade in France even though she didn't speak the language, did brilliantly in school there, and only started having issues when we moved to Germany... because those kids only have half day school.