Start by having students students try this challenge. After that, students will learn how to draw triangular numbers, and how to find the \(n\)^{th} triangular number by adding. For example, to find the \(4\)-th triangular number, we do \(1 + 2 + 3 + 4.\) Conclude by giving your students the challenges found here and here.

Conclude by leading this investigation:

Half Fraction Snake

by MathPickle