Answer: mrwizard

AnswerCrossword Clue
MRWIZARDTV scientist who debuted in 1951
MRWIZARDScience experiment conductor of kids' TV
MRWIZARDTV experimenter
MRWIZARDConductor of many TV experiments
MRWIZARDDon Herbert's moniker on 1950s-'60s TV
MRWIZARDMoniker of the author of "Experiments for Young Scientists"