Stephanie Rosalia, a librarian at Public School 225 in Brooklyn, teaches Internet skills.Credit...James Estrin/The New York Times It was the “aha!” moment that Stephanie Rosalia was hoping for. A group of fifth graders huddled around laptop computers in the school library overseen by Ms. Rosalia and scanned allaboutexplorers.com, a Web site that, unbeknownst to the children, was intentionally pepp