The source. Search for "RadioShack 200-in-One manual." Several users have uploaded complete, searchable PDFs. Because the kit is out of production (abandonware), these are generally considered fair use for educational purposes.
Before the era of Arduino, Raspberry Pi, and plug-and-play STEM kits, there was the . For decades, this iconic blue briefcase (often manufactured by RadioShack or Maxitronix) served as the primary entry point for aspiring engineers, hobbyists, and curious kids into the world of electronics.
If you are self-teaching, follow this sequence inside the manual: