This document discusses using GeoGebra to teach key calculus concepts like limits, continuity, differentiation, and integration: - Limits can be visualized using a rotating regular polygon to show the relationship between its number of sides n and a circle. - Continuity can be explored by drawing piecewise functions and moving points on the graph. - The derivative and its definition using slopes can be demonstrated by constructing line segments, points, and slopes on functions. - Integrals are represented using Riemann sums - the upper and lower sums are calculated and compared as the number of subintervals n is changed using a slider.