hello,
have you checked out International Islamic Grammar School? Its in F-11/3. The school teaches a child islamic education (quran, arabic, nazra and hadith) along with the British system of education (O-levels and will soon also have A-levels).
the website is:iigs.edu.pk
and address:
13, Main Double Road,
F-11/3, Islamabad
Phone: 2102423
i hope this helps!