Westborough – Traditionally each year, on the last day of school, Westborough Youth and Family Services hosts a special celebration to kick off the start of summer vacation. This year, plans called for the event to be held June 20 at the Bay State Commons Green. Unfortunately, Mother Nature sent an unwelcome guest – rain. Fortunately, the event’s organizers (WYFS, Westborough Recreation Department and the Westborough Public Library) acted quickly and the party was moved to the library. Over 300 kids stopped in to enjoy pizza and ice cream, play games and just relax with friends.