As Matt Birk spent the past couple of weeks pondering his football future, his mind kept drifting back to the immediate aftermath of the Ravens’ Super Bowl XLVII victory over the San Francisco 49ers nearly three weeks ago. For about 30 minutes following the Ravens’ 34-31 win, the veteran center lingered on the field at the Mercedes-Benz Superdome, huddling with his teammates, embracing family members and running and jumping around in a sea of confetti. “It is a great way to end it,” Birk said Friday. “No one is entitled to a Super Bowl, certainly not me. But I’m so grateful and fortunate to be part of the team. It is a special team and the run that we made, the championship we won is something I’ll never forget.” After 15 seasons, six Pro Bowl selections, one Walter Peyton NFL Man of the Year award and 112 starts to close out his career, Birk officially announced his retirement Friday. As he promised, the 36-year-old did it on his terms, making the announcement in front of a group of fifth-grade students at Battle Grove Elementary School in Dundalk. In saying goodbye to the NFL, Birk also announced that his HIKE Foundation will team with Scholastic to supply a “Reading Oasis” at the school. The reading center, which will be a place where students and their families can go to read, will be named after fifth-grader Larry Bryant, a student that Birk had grown close to during his career in Baltimore.