A Round in CritterCoin is a period of time during which points are accumulated by Houses and data is logged.
You can choose to manually reset your rounds or have CritterCoin automatically reset your Rounds on a fixed day interval. To setup automatic Rounds, visit the "Settings" section and choose the "Automatic" option.
When you end the Round, House points are reset to 0 and data is logged. Additionally, CritterCoin sends random Critters to all the students in the House with the most points.
Most schools set up automatic Rounds on a 7 day interval, but you can choose any option that fits your school's needs.