We moved our daughter and son from the UK education system to a co-ed school in Spain when they were 14 and 12 respectively.
They both did extremely well - better than we expected they would from results in the UK schools they had attended for the previous 2 years. They now both have good degrees, son has a Master's.
But. They went to an English speaking, fee-paying private school in Spain.
We never even considered sending them to a local school.
However, they both speak fluent Spanish and quite good French.
On some great and glorious day the plain folks of the land will reach their heart's desire at last, and the White House will be adorned by a downright moron.
H. L. Mencken 1880 - 1956
Some may not like his views, but what a prediction!