Class can have max 2 gaps per day

The software doesn't create gaps for classes and students by default, but calculates the average number of lessons per day and then it places them consecutively. This is ensured by so-called "Educational block". See this article for more information: Education block - Checking of gaps in class timetables

However if you need to have gaps in classes timetables, but you wish to minimize them to max 2 free periods in a day, you can do so in this way:

1. At first allow gaps in classes timetables with "discontinuous educational block". See: Education block - How to allow gaps in class timetables
OR
set, that some subjects can be in the afternoon. See: How can I define lessons that can be outside teaching block(in the afternoon)?

2. Now you can add use card-relationship "Max gaps per day" to minimize the created gaps:

Notes:
- this topic is for longer gaps, if you just need one lesson free for lunch you can do this directly:
How to specify when a class can have a lunch?
- the same card-relationship can be setup for individual students:
Student can have max 3 gaps per day