This project developed a lesson authoring system, a component which provided communications between students and teachers using electronic mail, and calculus lessons which were formatively evaluated with 20 students at four high schools. The authoring system utilized word processors to write the lessons and a BASIC computer program to execute the word processor files. Interactive lessons written on a word processor using one operating system were transferred to a different operating system using communications software. To maintain computer compatibility, worksheets were used to present graphics material. Students and remote teachers communicated through electronic mail (e-mail). The lessons saved student responses to questions in a form which was easily included in e-mail messages. The remote teacher wrote answers to the questions in a form which was returned to the student on e-mail. These answers were executable as lessons and merged into existing lessons using word processing functions. This created a dynamic software library which was updated as student questions were answered. This report includes the cost of continuing the course and the student evaluation of the course. (Author/YP)