I watched this television show in around the 1989-1994 period in the UK. It would have been on Children's BBC or Children's ITV programming. I think there were several seasons/series. In each season, the antagonist would somehow break up a magical artefact (something like a chalice) into several pieces (perhaps 6-10 pieces) and scatter them to different locations. In each episode of the season, the protagonists would find one piece, and in the finale bring them back together. I don't think the actual artefact they were seeking was actually that important in the end, ie it was a MacGuffin.
There were definitely some magical elements but the main protagonists were "normal" children I believe. My memory of this is very fuzzy so certain elements may be incorrect.