I think you will find that the young Obama attended the Fransiskus Asisi School in the Jakarta suburb of Menteng.
Now I’m not sure if your Indonesian is up to scratch or how strong your knowledge of Catholic saints is but I dare say you could still figure out that a school named after “Fransiskus Asisi” is not a ‘muslim school’, whaddya think?
He went to a Catholic school for three years, but went to a state school for a year after that. That was the school which was characterized by Insight Magazine as a “madrassa.”
What I’ve read from people on FR who have researched it is that 0bama went to the Catholic school first, and an Indonesian school after that.