One way to help learn about your students and their individual interests is an Interest Inventory. This can easily be incorporated into the first couple weeks of school when students are learning about classroom expectations.
In addition to having students complete an inventory, you can also send home an inventory for the parent to complete in order to give a complete picture of the child.
The answers to these questions can later be used to create a reward menu if you have a child that needs a more specific behavior plan.
Included is three inventories (1 for the parent and 2 for students). They are also included in black and white.