In Caesar 3, how many tiles do school children run?

I ran 20 tests on completely straight roads, placing a school at one end, such that only a single tile of the school is adjacent to the road. These are the figures I have come up with:

Tiles | Count 14 | 3 19 | 2 20 | 7 23 | 6 24 | 2

I have also observed the following scenarios:

• all children would run as a group and disappear at the same time
• some children run forward, while some turn back after 1-2 tiles, run to end of road and then turn back to the original direction
• all children run straight, all but one disappear early, and the last one continues for a few more tiles

Also if all schools were placed on the same X or Y coordinate, it seemed that they would have the same effective range on their respective roads.

Of course, each school only had a single route pattern, which never changed once the school was created.

Did anybody research this topic?