O Level schools are those schools that provides the Cambridge International Examinations, as you are looking to get the schools at the city of the Bangalore that provides the Cambridge International Examinations so her are some of the schools that you may like

The International School.
Address:
Behind H.L.L. Ltd.,
Near A.E.C.S. Layout
Near Dommandra Circle
Bangalore, Karnataka - 562125
080-22634900 till 980

TREAMIS World School.
Address:
Hulimangala Post, Jigani Hobli
Bangalore South, Karnataka - 562104
080-27803006, 9972399041.

Ebenezer International School.
Address:
Singena Agrahar, Huskur, Hosur Road,
Near Electronic City
Bangalore, Karnataka - 560100
80-41464326, 41464327.

Indus International School.
Address:
Billapura Cross, Sarjapur,
Bangalore, Karnataka - 562125
80-22895900

Sarala Birla Academy.
Address :
Bannerghatta, Jigani Road,
Bangalore, Karnataka - 560083
080-41348200, 080-41348203/04

Canadian International School.
Address :
Survey No. 4 & 20, Yelahanka
Bangalore, Karnataka, 560064
080-6451-4001/01/02/03/04/05/06/08

Buddhi School.
Address :
57, 3rd Main, 4th Cross
RMV 2nd Stage, H.I.G Colony
Bangalore, Karnataka - 560094
080-23518056, 23518057

Bangalore International School.
15 KM, Hosur Road, Kothanur Post,
Bangalore, Karnataka - 560077
080-28465059, 28465060.

Mallya Aditi International School.
Address :
121, 3rd Cross, Yelahanka,
Bangalore, Karnataka - 560064
080-28462850.

Jain International Residential School.
Address:
Jakkasandra Po,
Kanakapura Raod,
Bangalore, Karnataka - 562112
80-27577050 / 60 / 70 / 80

Primus Public School.
Address:
Chikanayakanahalli Village,
Off. Sarjapur Road,
Bangalore - 560 035.
Ph : 080-25741450, 25741452

India International School.
Address :
Sy No. 26/1, Chikka Bellandur Village,
Near Wipro Corporate Office,
Carmelram Post,
Bangalore, Karnataka - 560035
080-28439001/2/3, 55366001/2/4