I had a completely rose-tinted view of French education when we bought out 11 year old here and threw him into the deep end. I thought the fact that there were 24 to a class, meant that he'd get a good helping of individual attention.
He went to a rural collège where the headmaster once declared to me that, yes, he was indeed, discriminating against the foreign students because in his experience, they needed to be 'pushed harder'. He himself is Spanish.
If I had known how antiquated and authoritarian their system would be, I would have moved mountains, (definitely including our home), in order to send him to an international school if it meant ANY hope of him not giving up completely on getting any higher education at all. He is 18 now and HATES school. He left at 17. By that time it was too late, he'd given up on learning long before. He tried lycée and afterwards tried day release apprentiship but he hates the way he's spoken to. At home he gets respect and gets to express an opinion. At school and even at the training institute he gets treated like a dog. I blame us for being so naive and I blame the French educational set up, and the total lack of provision for foreign students in a rural setting. One or two of the french tutors did their best to give our son extra french tuition (one in particular was great) but generally, the attitude was "sit, copy from the board and listen. This is how we learn in France, not by doing, but by listening and shutting up."
When I suggested that my son was little more than a free educational assistant in every English lesson he attended, and that he really should be being challenged more by giving him separate assignments, I was ignored. If he hadn't been an obsessive reader and we had had an English TV for him to zombie out in front of instead of reading novels, he'd never have learned to read and write in English to an adult level either and I worry about his level there too. I doubt he'd pass an English GCSE.
My son would absoloutely say that he wished he went to school in the UK. He had 5 months in the UK not long after we moved here when we got stuck there due to a mix up over health cover. He regretted coming back and although a certain amount of his comparison between the two systems is definitely due to avoidance and teenage irresponsibility, I have to say I wish I'd stayed there too.
On the plus side, university is free.
My advice is go hard for an international school even if it means moving. But very good luck with whatever you decide.