Onionhead® is great for all ages, from 1 to 101. 
However, with all our present problems concerning children, we want to reach them as young as possible. The faster we teach them emotional knowledge and social skills, the faster we will help them have a more loving and successful life. Onionhead products are generally developed for “ages uo to 9″ (for children’s) and “ages 9 & up” (for teens and adults).
Pick up a feeling card and have them make the face, then say the feeling. Seth, a 2 year old child, did this all day long. He would pick up a card and mirror back the face. Then we moved into the exercise of telling him what the feeling meant every time he did this. He developed more emotional knowledge than any 2 year old we had ever seen.
Use the products the same way you would use them with anyone. Have the child pick out the emotions that she is feeling. If the choices are heavy, ask her to show you what she would like to feel. Then ask if she can describe why she (or Onionhead®) is feeling the heavy emotion. Some children feel safer expressing how Onionhead® is feeling. Allow them to speak through him. If they are all light, ask the child to share. Do this daily, or twice daily, and you will surely get to know this child. Children love choosing the cards because they feel they are in charge of themselves; it has proven to be self-empowering.