A dismissal schedule is a group of students and a time, for example "Lower School, 3:15–3:45, Monday to Friday." It does not decide where students are picked up. That's set on each student's weekly plan.
Step 3: Create a dismissal schedule
Go to Dismissal Settings → Dismissal Schedules → New Dismissal Schedule.
Name: for example Lower School Dismissal.
Schedule: switch on the days you need. For each day, set a Start Time, Duration and Parent Cutoff.
Transport options offered on this schedule, and the default transport. Leave it empty to offer every transport option in your school. If you choose a list, the default has to be one of them.
Who can view dismissal events? and Who can start this dismissal event? (see Permissions).
Status: Active or Deactivated.
About the schedule times
Parent Cutoff is the time after which parents can no longer change that day's transport. By default it's 30 minutes before the start time. You can also choose no cutoff.
Times must fall between 7:00 AM and 8:00 PM in your school's time zone.
When you set Monday, the other weekdays copy it until you change a day individually.
At least one day must be switched on.
Note: A dismissal only runs on a given day if the schedule is Active, that weekday is switched on, and it has at least one student.
Note: While today's dismissal is In Progress, you can't delete or deactivate that schedule, or add or remove its students.
Step 4: Put students on the schedule
Each student can be on one dismissal schedule at a time. Adding them to a new one moves them off the old one.
This step is done outside Dismissals, which is why people often miss it:
Go to Admin Console → Students.
Filter to the students you want (by tag, house, year group, or whatever you use for day students).
Select them.
Click the icon button with the tooltip Assign Dismissal Schedule.
Next, set each student's weekly plan so they leave from the right spot each day.