My son will 7 next month and he still likes PBS kids. Arthur is one of the shows on it and it's mostly about social rules, feelings and family relationships. Aboutface is an online game that "tests" you for your understanding of facial expression of moods, and their context.
For example, "D.W.'s friends jumped out and yelled, 'Happy Birthday!' How is she feeling?"
and three different facial expressions are given with their labels.
BTW, Arthur is populated with anthropomorphized animals, they're people with animal features but hands and feet. It's kind of weird but it allows you to focus on the stories rather than the appearance and it sneaks in diversity.