This is the first in a series of posts that will discuss issues relating to online teaching during the covid-19 pandemic.

There are countless issues that confront your students and one of them is access to textbooks. Although current courses have already adopted texts, student may not have their texts at home. You might want to give your students an alternative reference as you start working online. For mathematics, there are two collections of texts that contain virtually every topic we currently teach. In these sites, the books that are listed all offer free pdf’s and in most cases, online versions. The pdf versions are useful for students who don’t have high-speed internet access. The companion online versions use a bit more bandwidth, but have the advantage of having a variety of interactive features.

• The American Institute of Mathematics has an Open Textbook Initiative with curated list of open source textbooks.
• The PreTeXt project has a catalog of texts that have been developed with PreTeXt, an XML application that facilitates publishing a single source in multiple formats, including pdf, html, and Braille.

Even if you intend to keep using your current text, you might want make your students aware of these alternative resources.

The online versions frequently include editable code such as this page from a differential equations by Thomas Judson, which is listed on the PreTeXt site.