KGV or YCIS

my girl is in ycis now (year 8) and thinking to change to kgv next year (year 9)kgv already accepted my girl
but there are many rumours saying that kgv have many bad kids and people there are smoking and eating drugs
but ycis's English is way too bad
my girl don't even speak english at school (ycis) and instead speak mandarine
should i make my girl change to kgv
p.s she don't really mind changing
thanks a lot