The authors advocate that every primary grade program needs a carefully planned social-emotional component. All children--those who enter first or second grade with an ability to control their emotions and make friends and those for whom these skills are more difficult--benefit from intentional teaching in this area. Some school systems adopt a schoolwide approach to social-emotional learning, while others use a particular approach across a grade level. Three programs that may be implemented at grade level and also lend themselves to schoolwide use are: (1) Responsive Classroom; (2) Second Step: A Violence Prevention Curriculum; and (3) Interplay Solutions. In addition to using one or more of these programs, some school systems and some teachers develop their own activities for building a social-emotional curriculum. In this article, the authors describe these programs and a teacher-created activity and indicate how three Massachusetts school systems have implemented or been impacted by them. The authors conclude that programs like these help teachers move away from a fragmented and reactive approach to children's social-emotional well-being to a proactive approach and a shared responsibility for children's social-emotional health.