Just a Little Critter Collection by Mercer Mayer is a great collection with many character building stories. Little Critter teaches valuable lessons for young children. My favorite story is I Was So Mad. It teaches children how to cope with anger, and obedience.
Use in the classroom: I would use this in a reading center as a silent reading time. The students would have a character building week, and this would be the collection that they would read. They would read a different story every day for that week. They would talk about the story they read, and what lesson they learned from it.
Grade- End of kindergarten-1st