Lionard Pajoy also scored for Philadelphia in the 21st minute, and Sergio Escudero tied it in the 41st minute in Schalke's first game in the United States since 1963.
Philadelphia improved to 4-0 in international exhibition games at PPL Park following 1-0 victories over Celtic FC, Chivas de Guadalajara and Everton.
The game might have been the last for Schalke midfielder Raul. The Spanish star officially wrapped up his Schalke career Saturday. The former Real Madrid striker spent two years in Gelsenkirchen, and has said he might play next year in Europe or possibly MLS.
Schalke recently finished third place in the German Bundesliga, earning an automatic spot next year in the Champions League group phase.