Franciscus Bernardus Theodorus (Frank) Groothof Schröder (Amsterdam, february 14, 1947) is a Dutch actor, primarily known of productions focussed on children. He is known as 'Boy Zonderman' in the popular Dutch educational televisionshow for kids 'Klokhuis', and as resident of the Dutch Sesame Street (Sesamstraat). In the latter, he first played a mischievous boy, but turned into a young uncle. Groothof studied at the conservatory of Amsterdam for five years. After, he joined a musical and worked for twelve years with 'Het Werktheater', performing lots of theatershows and movies.