A teacher distributes different types of triangle shaped paper cuttings to the…

Teaching methods are classified by how learners arrive at a rule or principle. In discovery learning — an inductive, activity-based method — learners are given materials and a task, then investigate directly, collecting and analysing their own data, to arrive at the underlying rule themselves rather than being told it.

Here, each learner receives several different triangular paper cut-outs, measures the three angles in every triangle, and tabulates the results. No one gives the angle-sum rule beforehand — the learners infer it purely from the pattern in their own recorded measurements. This self-directed, activity-based route to a generalisation is exactly what discovery learning describes.

• Teacher centered approach: the teacher actively explains or demonstrates the rule while learners mainly receive it; here the teacher only sets up the activity and never states the relationship being investigated.

• Deductive method: teaching moves from an already-stated general rule to specific examples that apply it; here no general rule is given first — the sequence runs the opposite way, from individual measurements toward a generalisation.

• Analytical approach: an existing complex whole is broken down into its component parts to examine how they relate; here there is no given whole being decomposed — learners are instead generating fresh data across independent cases to build up a pattern.

So the activity described is best classified as discovery learning.