There are several depictions of the world map. The most common has the mass of the earth inside a rectangle. The centre of the image, a normally privileged place, is occupied according to the surrounding culture. In the American culture, the central continent to be depicted is often America, and in Asia the same attitude is noted. The European culture isn’t an exception.
Part of being European is to imagine ourselves, at least graphically, in the centre of the world map. Whether because we’ve been taught this way, or because we’re constantly bombed by that same image divided by the Greenwich semi-meridian, also suggesting a temporal reference.
So, in order to get a participative support, I suggest that you mark Europe on an empty map, free from instructions, whether cardinal points, or the goal of map itself. In this manner, the participants are finally free to make their own drafts.
Now, without resorting to graphics, would you still mark Europe in the centre of the world?