Calendars and Service Periods are required in order for your data to properly be displayed in online applications.
Create a New Calendar
New Calendars can be created by selecting Add Calendar. The only available field on a Calendar is Name. Name your Calendar something that clearly identifies what function it serves (such as School Year or Winter Shuttle.)
Service Periods determine when a Calendar is in effect. A Calendar may have any number of Service Periods, provided they do not overlap.
On the desired Calendar, select Add a Service Period and select a start and end date. Depending on the type of Calendar used, multiple Service Periods may be required (such as a school Calendar that only operates when school is in session.)