Explain the basic concepts. While an approach that includes several ways of learning will ultimately be important, kindergarten students should be able to get a basic understanding of key concepts such as: mother, father, son, daughter, grandmother, grandfather, uncle, aunt, cousin and family. When introducing these concepts, relate them to the student's life, asking them to think about the people in their own lives.
Use pictures and stories. Once students have a grasp of the basic concepts, have them draw pictures of their family and then share some stories about who their family members are, what they do and how they interact with each other. Of course, these pictures and stories will be basic, but they will get students to start thinking in a simple way about relationships.
Sing songs. Songs will help students learn about children and family, too. Teachers can lead the students in song, several of which are available online. For simple songs, the words can be written on large cue cards and posted around the classroom. This will also help students develop their reading skills.
Involve families. Teachers, of course, are not the only educators in a kindergartner's life. Ask family members to get involved with teaching their children about families. Parents can visit the classroom or homework can be arranged, asking students to spend a few minutes talking to their family members -- in simple terms -- about their family and who comprises it.