The more tools you have in your play therapy tool box the more likely you will be to select an activity that meets the needs of a specific child.
The book, Techniques-Techniques-Techniques: Play-Based Activities for Children, Adolescents & Families by Sueann Kenney-Noziska features a tool for assessment and engagement that I use often in my practice. It's called, "Ice Breaker" and it utilizes the Hasbro game, Don't Break the Ice.
The basic premise of the game is that colored stickers are placed on the underside of the game ice cubes with each color corresponding to one of six categories. As players knock ice cubes out of the game, they shared something about themselves based on the color of the the sticker. You can read specific details of how to make and use the game on the Infinity Publishing web site.
This is an easy and affordable technique to create and it's adaptable to the population you work with. The only challenge to this game is actually setting the game up and putting the ice cubes into position. Many young children find this difficult so I use that as an opportunity to discuss frustration tolerance.
If you use this technique I'd enjoy hearing your comments on how variations of this game and how you find it helpful in regards to assessment and engagement strategies.