The Case of the Counterfeit Criminals (The Wollstonecraft Detective Agency, Book3)

This “winner” (School Library Journal) of a history-mystery-science series continues as the Wollstonecraft Detectives—Ada Byron Lovelace and Mary Shelley—take on a case from the celebrated dinosaur bone hunter, Mary Anning.
 
The Wollstonecraft Girls embark on their most important case yet—the famed dinosaur fossil hunter Mary Anning is being blackmailed. Her precious dog has been snatched and the kidnappers are demanding that Miss Anning authenticate some fake dinosaur bones up for auction at the British Museum in order to get him back. Ada and Mary have just three days to track down the fossil fakers, find the dog, and save the integrity of science!
 
The game is truly afoot in this quirky caper involving blood-sucking leeches, an asthmatic pug, smoke bombs, secret elevators, diabolical disguises, and wicked word-play.
 
Praise for The Case of the Missing Moonstone:

"An enjoyable plot, resourceful heroines and fun writing."—Wall Street Journal
 
"Smart and witty. . . . The detectives in training use quick thinking, book smarts, and social know-how to find a stolen gemstone. Comical narration and dialogue will charm readers thoroughly."—Publishers Weekly
 
Praise for The Case of the Girl in Grey:

"Mystery fans ... will relish the girls’ romp around the stately home; discovery of an encrypted clue (in the crypt, of course); and unraveling of the mystery."—Booklist
 
“Equal parts laughs and adventure, this lively mystery will keep you guessing till the end!” –Discovery Girls