Students at PS 106 in Far Rockaway, Queens, have gotten no math or reading and writing books for the rigorous Common Core curriculum, whistleblowers say. The 234 kids get no gym or art classes. Instead, they watch movies every day. “The kids have seen more movies than Siskel and Ebert,” a source said... The principal — Marcella Sills, who joined PS 106 nine years ago — is a frequent no-show, sources say. Sills did not come to school last Monday. On Tuesday, she showed up at 3:30 p.m. On Wednesday, The Post found her at home in Westbury, LI, all...