My children ( both of them ) are studying in Gateway school , at their Sholinganallur campus. The school has 3 campuses , I think each is dedicated to a different curriculum ; the one at Sholinganallur follows the IGCSE , the one at Padur the CBSE , and the one at Neelankarai the American. Please check their website http://www.gatewayschools.in
There are pros and cons about this school ; firstly , we have a vested interest in this school ! We first came to this school in 2007 , where they gave our children a double promotion when our children transferred from another school. Our children were given a second double promotion in 2010 ! Both these were totally unexpected , and I don't think any other school would do this.
Now that this is out of the way , let us get down to brass tacks ; the school infrastructure is decent , neither too good nor too bad. The teaching is quite good , the number of students in each class not more than 15. The teachers are nice and there is a friendly relationship which you won't find in the bigger schools.
Activities are not so many , though the campuses have swimming schools. Karate , chess , yoga are available , but not in a very competitive fashion.
If you want your child taught in a friendly atmosphere , totally free from any common vices such as smoking , drugs , then Gateway fits the bill ; both my children have had fun learning throughout their stay there ; they are at present in Class 10 and Class 11.