Kenneth Merrell's "Strong Kids" is a solid social-emotional learning curriculum (designed for classroom implementation, but no reason you couldn't adapt it for home use) for this age group. Not specifically about moral reasoning, but has relevance for related topics.
http://www.amazon.com/Strong-Kids-Emotional-Curriculum-Curricula/dp/1557669309Arnold Goldstein's Equip/Prepare curriculum, designed for delinquent adolescents, might be a bit of overkill, but it does include moral reasoning as one of its three prongs (social skills, in the form of Skillstreaming, which I've referenced elsewhere, and anger/aggression control are the other two prongs). "Aggression Replacement Training", by Barry Glick and John Gibbs, is the updated version of this, revised after Dr. Goldstein's death.
http://www.amazon.com/The-Prepare-Curriculum-Prosocial-Competencies/dp/087822419Xhttp://www.amazon.com/Aggression-Replacement-Training-Comprehensive-Intervention/dp/0878226370On a different note,
www.emotes.com sells fun, child-friendly products and curricula for social-emotional learning, which also overlaps with character education. I haven't actually used their products (unlike the Goldstein and Merrell curricula), but what I've leafed through at convention exhibit halls looks promising, and very appealing to children.
I would imagine that some of the critical thinking products (such as from Critical Thinking Company) could be useful in moral reasoning.