What does a teacher/student do when his students don´t come to school?

As usual I arrived l to the school, I was going to have just one group (the other groups were not attending school for God knows what the reason is). So I came to school for one single class. The bell rang and I didn’t see any chlid coming to the classroom, that, by the way, was closed. Soon one teacher told me that neither this group nor the others would come to class today.

What should I do? I have all the morning free. They wanted me to stay there and teach their own groups, but I had some other activities to do.

I know I should be planning or doing my homework (I am a student too), but I prefer to stay at home with my girlfriend and eat breakfast together.

See you! and Happy unexpected day off for myself.