Singer Colby O’Donis, best known for joining Lady Gaga on the hit “Just Dance,” performed in a talent show for the now 20-year-old organization BELL (Building Educated Leaders for Life) at the Revere Hotel over the weekend. Joining him for a performance of that song was BELL scholar Angelica Estrella. Other entertainers at the party included the a cappella group Pitch Slapped, which had just performed the national anthem at the Celtics home opener. Money raised from the night will go to after-school and summer programs for local kids.