Boston Children’s Museum celebrated the 100th anniversary of Fenway Park with “Play Ball,” a Friday of baseball-themed activities and appearances by Wally the Green Monster. Kids had baseball story time, took photos with World Series trophies, designed their own team T-shirts, and dressed up like a ballplayer. Zachary Maurice (right), for instance, suited up to play catcher. Other children at the museum included Liya Quebedeaux, 2, (above) who brought her mother, Liliya , to meet Wally.