In Billing Rate Conditions you can add, edit, or delete billing rate conditions. Billing Rate Conditions can be used to setup any different kind of discount or variation on the charge of the existing Billing Rates. These Billing Rate Conditions rely on internal system formulas to determine who they should apply to. A common example is a multiple child discount where the second or third (or more) child receives a discount on Tuition and this can be setup for those. The birth order in student setup helps with this.