Salam,
Good education is hard to come by now a days as it has become an industry just like people coming from UK would know. If to anyone who has no issue with dishing out close to USD 6000 a year then i would suggest (aged under 5/6 years kid)
-
Sheikh Zayed International Academy-Islamabad (www.szia.ae) (The best school there is Hands down minimum fee is close to USD 6,000/year/kid)
2. ACE Bahria (www.aceia.edu.pk) (The next best option but for people in islamabad you kid will have to travel almost 45-60 mins plus Faizabad point is usually closed due to any small or big protest which will add to the inconvenience, oh and its close to USD 3,000.year/kid)
- Edopia (http://edopia.org/) (Based on Harvard Project Zero, for early childhood development, a different concept, based on project based learning but very good)
Rest i guess Treehouse is over rated coz if there are 20+ kids (pre-school and kindergarden) in a class, with one teacher, i would not pay them USD 3,000/year
- PSI in diplomatic enclave was and still is a good option
But all i can say that Please visit, meet the teachers, not just the teachers for your kid's class but 2-3 years ahead of his current class, coz you donot change school very often need to know if they have quality teachers throughout the classes. Put your kid in a schoold you feel comfortable after taking to teachers and pray to Allah Almighty that he gives His Rehmat and Blessing in your decision.
on a side note: only few schools have big enough campus to support a decent courtyard, let alone playing field.