I'm assuming the Ara
I'm guessing the kids weren't familiar with a white person knowing something about them in that kind of way. They probably just thought it was a bit odd, but I wouldn't focus too much on that. You could always learn some Somali, as most Somalis probably don't know much Arabic beyond the basics, unless they come from an educated background (Nabid=hi, wa fiyantahi=how are you?). Volunteer at a refugee camp, or something similar. I think you would find it very rewarding to partake in another group's culture (you seem to have the curiosity for it), and it's always flattering when someone takes the time, effort, and interest in another culture.
At the end of the day, people are just people. As long as you proceed respectfully (which it seems that you have) and with curiosity, you really can't go wrong. I would caution with speaking too openly with women (generic greetings are fine, but engaging in full conversations before having a working knowledge of gender roles/proper etiquette may make some people feel uncomfortable). Sporting events are always great ways to socialize.
Good luck!