What is referred to by 'a professor or principal'?

Based on the clue 'a professional sports athlete no longer under cont...', what is the answer? What is associated with: a professional tap dancer from age 5 he got his own cbs sitcom in 1997? Based on the clue 'a professionally prepared evaluation that estimate...', what is the answer? What is associated with: a professor 1967 turn on tune in drop out? What is associated with: a professors 2007 address at carnegie mellon on really achieving your childhood dreams inspire… What is associated with: a profile of this film director says he was born in britain in 1899 died in los angeles in 198… What is associated with: a program on ocean liners featured this ship seen here ishe could carry 3000 passengers crew i… Based on the clue 'a program that constantly shifts the pattern on yo...', what is the answer?