If you're not following the latest chapter in John Allison's Bad Machinery, titled "The Case of the Fire Inside", you are seriously missing out. The fine collaborate at Wikipedia sums up the stories thus far:

The two groups of child investigators attend the fictional Griswalds Grammar School in Keane End, Tackleford. The groups interact and compete to solve the mysteries, even keeping a tally on a wall. They are, however, not always aware of each other working on the same mystery or dilemma because they start at different ends, the boys being fixated with catching monsters and the girls more often following their emotional connections.
Bad Machinery focuses on humour, with funny and surreal situations, punctuated by moments of action and mystery. Every episode has humour in it, and the artist will frequently add visual jokes in the background. Bad Machinery is also proudly British in its sensibilities.