The adventures of Sheldon Cooper when he was a boy? That's what you get with CBS's hit "The Big Bang Theory" spinoff/prequel, which looks back at the socially inept physicist when he was a 9-year-old prodigy (Iain Armitage) attending high school in late-'80s East Texas, and presenting upbringing challenges for his protective mom (Zoe Perry) and football coach dad (Lance Barber). Montana Jordan, Raegan Revord, and Annie Potts co-star, with narration from grown "Sheldon" Jim Parsons.