To customize an existing interaction: 

• Go to the class page
• Click on the Settings Wheel in the top right corner
• Click Edit Settings
• Click the Interactions tab
• Click Edit Interactions
• Click on the award you want to edit
• Choose Interaction Sticker
• Edit Name
• Edit Points
• Click Save

Additional Resources:

• Adding, Editing, and Deleting Flags in Behavior in a Classroom
• What is the difference between community flags and my custom flags and awards?
• How to add new Interaction/Award types