At the beginning of his career his popularity quickly grew, causing networks like CBS to create and implement multiple television series specifically for his involvement and leading roles.

"[1] In 1978, McNichol recorded an album with his sister, Kristy, also a child actress, and the two went on to host a youth-oriented variety show for ABC.

McNichol subsequently had lead roles in Smokey Bites the Dust (1981), and opposite Susan Tyrrell in the horror film Butcher, Baker, Nightmare Maker (1981).

After retiring from acting in the 1990s, McNichol relocated with his family to Colorado, and has been active in environmentalist causes, and working as a real estate investor and home renovator.

[7] McNichol was raised by his single mother after the children's father, a carpenter, abandoned the family shortly after Tommy's birth.

[12] The siblings also appeared as co-hosts of the fall 1978 ABC All-Star Saturday Preview Special, a youth-oriented sketch comedy show featuring musical guests such as the Bee Gees and Donny Osmond.

"[15] When California Fever ended, he won the role as host of a weekly talk show, Hollywood Teen, as well as the Jimmy McNichol Special, which first aired in April 1980.

[18] He subsequently appeared in several other successful made-for-TV movies, including the thriller Blinded by the Light (1980), in which he starred opposite his sister Kristy as a gay teenager who escapes a religious cult.

[24] In 2010, he discovered he had a third child: daughter Kellee Maize, a rap artist, songwriter, and entrepreneur from Pittsburgh[25] who had been raised by adoptive parents in Pennsylvania.