In the Fall of 2019 I began teaching the year long sequence course Math 271/272 at CSU titled Applied Mathematics for Chemists I/II. This class is rather new. It had only been taught by three others before me and had only ran for four years. I challenged myself to build this class in my own way by bringing my own insight to the content.
Having taught Math 255, Calculus for Biological Sciences II, just prior to the chemistry version, I had some TeXed up notes prepared. Students are already paying thousands of dollars to enroll at a university. I figured that the least I could do was provide them with a free textbook of my own notes. So, my notes became the foundation for the course and I created homeworks, quizzes, exams, and projects to make the course complete. The advantage here is that the content is streamlined -- it is specifically catered to this class sequence and has no unnecessary material. Homeworks, for example, build off one another and problems are rehashed in new ways throughout.
As of late 2020 I decided to release this textbook publicly on Github. Here is a link to the text: Applied Mathematics for Physicists and Chemists. There is still much to do. I have started placing the problems I've written in the corresponding sections and I have outlined a few changes that should be made. I believe this text can be used widely and updated by any interested party. I do not need to claim complete ownership. I prefer everyone has their chance to use the material if they so wish.
Along the sidebar you can visit the various semesters for the course sequence. You can see the class progression throughout. I have learned a ton from my students and I deeply appreciate their input. From countless typos they've found, to suggestions about the content, and to returning during later semesters to be TAs for the class, I owe each one a debt of gratitude.