When coming upon a feature in the terrain an orienteer should be able to identify whether or not it would classify as a distinct linear feature.
At the same time kids should be learning to independently recognize features on the map as linear.
The following links point to resources that have been collected and are relevant to this skill (?).
Description of / instructions for a simple 'handrails course' exercise complete with warm up activity to teach the concept of handrails at Orienteering.ca.