Set up Alternate Schedule days
1. Click on the Go To menu and select "Classes".

2. Click the "Schedule" button near the upper-left corner of the screen and select to "Add Alternate Day".

3. Enter a name and description (optional) for the Alternate Day schedule. Click the apply/save button when finished.
4. You should now see a list of your classes. Click the "Teach" box to the right of the class names to add those to the alternate schedule day. Then, enter times for the special schedule in the time slots towards the right of the "Teach" box.

Note - You can also use the grid button

The changes will save automatically as you enter these. When finished, go back to your plans.
You can then add an "Event" to quickly set up an alternate schedule day. Just select the alternate schedule day you wish using the Alternate Day drop-down menu. When saving the event, the alternate schedule will be applied to the dates of the event.