This book is a nominee for the Agatha Awards in the childrens/young adult category.
Another title in the same series is also up for the award. I skimmed that one, assuming it was the first in the series, but there's an earlier one which I'm not bothering to read.
My main issue is that the mystery was minimal, if there at all, so it flummoxed me that it was considered for an Agatha.