Pittsburgh - Just shy of midnight on April 26th, David Klahr of Pittsburgh, Pennsylvania, renowned developmental psychologist, husband, father, grandfather and devotee of curiosity, died at 86. He was born on July 9th, 1939 in Springfield, MA, and was raised in Stamford, CT. David earned his undergraduate degree in Electrical Engineering at M.I.T., and a Ph.D. from Carnegie Mellon's Graduate School of Industrial Administration ("GSIA", now the Tepper School of Business) in Organizations and Social Behavior. For over 40 years, David was a beloved professor in Carnegie Mellon University's Psychology Department, where he served as Head from 1983 to1993. It was no surprise that, with his inborn inquisitive and playful nature, his research focused on investigations of how children come to understand the fundamental principles underlying scientific thinking. David was a pioneer in many aspects of his field; in 2009, the 37th Carnegie Symposium on Cognition honored David's contributions by organizing a three day symposium in his honor. In addition, he was the first member of CMU's faculty to be elected to the National Academy of Education. These are only a few of of the numerous professional celebrations, honors, and awards that David received during his decades-long career. David was deeply devoted to Pam Weiss, his wife of 45 years. For nearly all those decades, they lived together in the big red and white house at 1212 Heberton Street in Highland Park, and could often be found walking hand in hand through the neighborhood and around the reservoir. A consummate storyteller, David also took great pleasure in reciting poetry aloud—some of which had been memorized since childhood—and his recitations could take you by surprise at any moment. He loved spending summer months at Chautauqua Institution, listening to lectures in the morning and sailing in the afternoon, bicycling around the grounds. David's love of inquiry, analysis, language, and endless singing made an indelible mark on his four children, Anna, Josh, Sophie and Ben, and they carry forward that spirit of inquiry in numerous ways - from big data and social work to rock and roll and poetry. His creativity was boundless; a mind like his had no use for being bored. David's unconditional love for his children was unassailable, and he supported every path that they ever were curious to follow. He is preceded in death by his parents Alexander and Lillian Klahr, and older sister Helen Hirshhorn. He is survived by his wife Pam Weiss, his children Anna, Josh (Suzanne McKechnie Klahr), Sophie and Ben Klahr, his grandchildren Alex and Julia Klahr, and his step-grandchildren Desmond and Sedona Reilly. The funeral will be on Wednesday, April 29th at RALPH SCHUGAR FUNERAL HOME, 5509 Centre Ave, Pittsburgh, PA 15232, (412) 621-8282. Visitation will be held from 10 to 11 AM, and a service will be held at 11 AM. In lieu of flowers, donations may be sent to any of the following organizations and institutions: Carnegie Libraries of Pittsburgh, Congregation Dor Hadash, Chautauqua Institution, and Pittsburgh Parks Conservancy.