One of my best learning experiences, surprisingly, came from a subject that I was not very fond of. History lessons were always an ordeal for me because they meant reading from the text book and memorising a lot of dates and places.
That changed for me completely when we had a substitute teacher take our classes for a month in Standard IX. She transformed the lessons into an enjoyable exercise where we were required to search through different text books of Indian and World history to design a wall chart with timelines that marked incidents happening simultaneously in the world. It was an experience of immersion into the whole subject, researching the time periods and feeling accomplished; and suddenly it wasn’t boring anymore. 
The things I learned in those few weeks were effortless, and even after all these years, I still remember it all. This experience has led me to believe that learning doesn’t have to be boring, dull and coerced, irrespective of what the topic may be.

A negative learning experience I can recall happened many years later as an adult learner. I had registered for a Management workshop conducted by a reputed coach and was really excited about it. 
Unfortunately, it turned out to be a poorly planned event with too many participants to make it a productive session or to allow for participation. Hence, the entire day’s workshop revolved around some slide displays with poor flow and content, and the coach’s monologue, with no involvement of the audience. There was one opportunity offered at the end of the day to ask questions, and no one asked any. 
I learned from this experience that as learners, we need clarity on the objectives of the program, a chance to be involved in the learning process and interact with fellow-participants, with some activities and mind games, which can have add real value to, than to spend the day listening to something one could read on their own.