If you are facilitating a training session where there will be smaller break-out groups using a flip over charts you should think about where to position these flip over charts in the room.
Not only the light is a factor to consider (can the participants clearly see what is written on the flip over chart?) but also if there is a person presenting what is written on the flip over chart or is the group speaking about what should be written the flip over chart and the person standing next to the flip over chart is simply writing this down? Based on this you can determine if the sound (speak) is directed to the flip over chart of from the flip over chart. With this knowledge you can decide where to put the flip over charts in the room. In the corners of the room facing the middle of the room (when voice is directed to the flip over charts) or in the center of the room facing the walls (when voice is directed from the flip over charts to the participants).