23 - Signal in the Dark by Mildred A. Wirt Benson

Over a school holiday, young Penny persuades her father to let her work as a junior reporter at the local newspaper, the Riverview Star. Battling workplace rivalry and navigating the world of journalism becomes even more challenging when she lands her first major assignment - investigating an explosion at the Conway Steel Plant. As she aids a struggling colleague, she stumbles upon a fraudulent plot to sell a counterfeit explosive device. In a thrilling climax, Penny unveils the scam, bringing the perpetrators to justice!