Valentines day friendship activity a crack the code digital math challenge for 5th graders. Valentines day sub plans and upper elementary valentines activities: Make practicing data and averages engaging and interactive this Valentine’s Day with the Be Mine or Decline Digital Math Game! In this fun, video game–style activity, students work through Grade 5 problems focused on finding the mean (average) and decide whether each completed problem should be accepted ( Be Mine) or rejected ( Decline