David Ortiz autographed hats for students at the Hurley School in Boston Wednesday. The legendary retired DH joined a group of city, school, and Red Sox leaders — including Martin J. Walsh, Boston mayor, and Tommy Chang, school superintendent, — in their bid to reach out to a new generation of potential baseball fans. As part of that effort, the team and JetBlue are donating Red Sox hats to more than 45,000 Boston Public School students. Meanwhile, all Red Sox fans, new and seasoned and young and old, best heed the weather report and dress for a chilly day at Fenway Park Thursday for the 2018 season opener, which could be among the coldest in the past 11 years.