How to Be a Friend: A Guide to Making Friends and Keeping Them (Dino Tales: Life Guides for Families) By Laurie Krasny Brown, with pictures by Marc Brown, is a great book for ages 4 – 8 years old about how to build friendship skills. I highly recommend it for ideas not only on how to get a friend (asking someone to play, for example), but also because it talks about what a healthy friendship is. In the book she writes, “Anyone who is nice to you and likes to play with you can become a friend.”
When I talk with children about developing health friendships, one activity I enjoy sharing with them is to ask them to create a symbol or word that shows what friendship means to them. This is one example a child in the Respect Program created:

Don’t forget to be creative today!