This "Worry Tree" is a poster I would love to hang in my classroom. It is a resource I think students could refer to, when needed, to help them regulate their emotions and deal with their "problems" in an effective way. Eventually, they will be able to follow this process on their own, and develop their emotional competence - which is an important skill that underlies positive mental health (Reinke et al., 2011).
Feelings Game: Here are a range of worksheets developed by the Children's Involvement Team, to aid direct work with children and young people. The worksheets are all around children's wishes and feelings.