It is important to remember the way you react to them doing things such as telling on each other in situations like the one you described will help influence their behavior for similar situations in the future. If that happens again make the students aware that them telling on each other is not how you want them to act and provide them with details on what you expect in that situation.

To reduce blaming among second graders, establish a classroom culture of respect and responsibility. Involve students in creating classroom rules to enhance ownership and understanding. Use role-playing to teach conflict resolution and emphasize the importance of empathy and emotional self-regulation. Recognize and praise positive behavior and collaborative problem-solving. Regular class discussions can help reflect on and improve behaviors, fostering a more harmonious classroom environment.

I would remind the class that the only business we should be worrying about is our own. Tattling should not be happening and the only time they should tell the teacher about another student is if they are injured