Back then he and I were in email contact extensively. He recognized that we were doing similar things; I was doing the geometry section, he the calculus, both with a similar approach. He suggested at the time that they should be combined, but other priorities intervened and that never happened, and we lost contact. Sadly, I later learned that he had passed away in 2008 after a long illness.
However, I recently received an email from a teacher who had stumbled upon his original work. On investigation, it turned out that he had placed it all in the public domain, with instructions that it can be used for any purpose by anyone. After long thought, I decided that it would make a good foundation upon which to build the calculus section of the site.
So what you see now is the first phase of that process, in which the material has been extensively edited to conform to the style and appearance of the site. The content however is mostly unchanged.
There is still much to be done. The material needs to be cross-linked to the rest of the site. Many word definitions are missing. Eventually, like the rest of the site, the applets will need to be rewritten in HTML5 to make them available on tablets. Content could be expanded.
One area where the calculus section differs is that it takes a 'course' approach to the work. That is, it expects the user to go through it in a certain order, and each page builds upon the earlier ones. This shows up as the "next" and "previous" buttons on each page.
On the other hand, the content that I have written was designed so that each entry is more free-standing. You can jump in anywhere, and underlying concepts can be explored by using the extensive cross-links.I am not sure which approach is best. The existing material could be retrofitted into more of a 'course' style, or the calculus entries could be made more free-standing. Perhaps both styles can be used on the whole site. As always, I would appreciate your opinion.
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