Although the University had previously refused to let his father enroll him at age 9 because he was still a child, Sidis set a record in 1909 by becoming the youngest person to enroll at Harvard University.
Kuigi ülikool oli keeldunud teda 9-aastaselt ülikooli vastu võtmast tuues isale põhjenduseks, et ta on alles laps, tekitas Sidis 1909. aastal pretsendendi, saades 11-aastaselt noorimaks isikuks, kes on Harvardi ülikooli astunud.