In class VI, in the unit of 'Understanding Quadrilaterals', important results related to angle-sum property of quadrilaterals are introduced using paper folding activity followed by the exercise based on these properties. At this level, proof of the angle property is not given, as the students of class VI are at Van Hiele level of
Level 2-Informal Deduction
Level I-Analysis
Level 3-Deduction
Level 0-Visualisation