Webwise (focusing on internet safety and cyber-bullying) - http://www.webwise.ie
The Walk Tall programme (You can Google this)
The Stay Safe programme (You can Google this too)
The Cool School Programme (You can Google this too)
The Peace First website (you can Google this too)
The "Zippy's Friends" programme (You can Google this too)
The "Talkabout for Children" series of books that might be already in your school, by Alex Kelly, (available to order from www.speechmark.net), contain materials that you can photocopy for use in a class group.
Prim-Ed Publishing provides in book form excellent photocopiable anti-bullying resources (http://www.prim-ed.com/ie/catalogue/sphe/bullying) and conflict resolution resources (http://www.prim-ed.com/ie/catalogue/sphe/conflict-resolution).