Drop in at, drop in on

Yesterday morning, I went to the dance studio to take a basic dance lesson.

In the afternoon, I hosted a Chinese gathering at our cafe, two people participated, so I was happy enough.

In the evening, a client dropped in at my office.

This morning, I'll do the laundry, afterward, I am planning to host an English gathering at our cafe.

In the afternoon, a middle school student is scheduled to come for lesson, then I'll do a Korean lesson for a part-time student.

I am planning to go to the chapel in the morning and evening.