This might sound super vague but I barely remember this show. There was this show with 3 kids, one white boy, a white girl and a Black boy. I think the two white kids were siblings. I kind of think that it was a sci fi show and it might have been based on a book series. I think the kids were able to get their hands one some alien hardware that they could use to fight aliens. Think the kids wore uniforms to school, so it think they were private school students but they weren’t boarding school student. I believe the show came on showtime early in the morning. I remember watching in the early 2000's I want to say 2003 or 2004. I think the show was filmed in Canada or the UK. It was a 30 min monster of the week type show.
Unfortunately IMDB doesn’t have message boards anymore and I’m not sure where else I could ask so I thought I would give GT a try.