This paper describes the authors' use of MathView to create interactive web-based mathematical explorations for discovery-learning activities in courses such as calculus and linear algebra.  In the paper we show how to create interactive MathView notebooks for the product rule and for exploring the geometry of linear transformations in the plane, and  also show how to include live notebooks in a web page.  The paper was presented at the 1999 ICTCM in San Francisco, and has appeared in the proceedings of that conference.