I remember a series of children’s mystery books from when I was in 1st grade, which would’ve been 1987-1988. Each book in the series had the same color hard cover. The hard cover was thin and maybe glossy. I remember a series having an orange cover, but there was a different series from the same author or publisher that had a different color hard cover.
From my memory, I seem to remember there being a British-ness to the books. Some took place in a city, others in the country.
I remember liking the books and now that I have children, I’d like to read these books to them.