Don joined the Computer Science Department as a Lecturer after receiving his Masters Degree in Computer Science from North Texas State University (now UNT) back in 1978. Since that time, Don has taught a large variety of the undergraduate courses in the department. He is best known for developing several key courses in the department, including CSCE 4410 and 4420, the Software Development sequence where students write large-scale applications. He has also produced other courses, including the Computer Programming for Non-Majors (1020), Assembly Language Programming (2010), and most recently the Internet Programming Course (3420). His interest has always been in teaching programming languages, and throughout his tenure he has taught programming languages included FORTRAN, Pascal, C, C++, Java, and the most recent and his favorite, PHP. In recent years he authored the textbooks used in the 1020 and 1030 courses.
Don is also known in the department for developing many software-related tools to help with teaching courses, as well as other applications to assist the department itself. These include the WebCompiler environment and the ABET Course Assessment Management System. Don has been the departmentís webmaster since the department first had a web presence, also being one of the first departments in the university that had a website.
Don wishes to thank several Computer Science faculty members that have given him unrelenting encouragement throughout the years. These include (but arenít limited to) Dr. Jim Poirot, Dr. Denis Conrady, and Dr. Tom Irby. He also would like to thank his dad who always encouraged him in his various endeavors, no matter how odd they may have seemed at the time. Don feels blessed by the many friendships heís made, and fortunate to have been given the opportunity to teach such a wide variety of excellent students.
With his retirement, Don plans to continue developing code and writing books, something he’s been interested in for many years. You can view a list of Don’s publications here. He is in the process of publishing on the web all of his course-related material that he has put together during his thirty-five years in the department. He will continue to be his family’s historian and maintain the family website here. He also plans to travel extensively with his wife Elisa between doctor visits. The department has lost an important teaching asset, yet we wish Don well in his future endeavors.
Don has also setup his own version of the CSE Department's Media Gallery that was removed when the department went with a new version of the department’s website. You can see his newly-revised media gallery site here.
Would you like to leave any comments or remarks to Don? Please use the form below to send your remarks:
March 9, 2019 Pavitra Amin Graduated: 1994 Courses taken: Command Languages
Dr. Retzlaff (yes you deserve that title) - Congratulations on your retirement. Though my memory is fading, I still keenly remember your office across from the GAB 3rd floor lab. You were the "go to" teacher who was always interested in the latest tools, languages and embracing new ideas and courses. I really enjoyed the Command Languages course you taught — writing scripts helped me in the real-world. I’m still grateful for your help on my master’s project in C++. You will forever be remembered as not just as one of the best CSCI teachers at UNT but as a mentor to students who shared a sense of humor and understood their struggles.
September 26, 2017 Dick Hamilton Graduated: 1980
Hi Don, Congratulations (rather belated; I just stumbled upon this site) on 35 years with UNT and your retirement. It’s hard to believe that it’s been that long since we were taking classes and teaching together at NTSU :-). Best wishes for a happy retirement for you and Elisa. Dick Hamilton
July 7, 2014 Amanda J. Stiles
I didn’t realize how much you contributed to my successful career, until I saw the writeup in the UNT CSE newsletter, Spring 2014. I took several classes from you while I was working toward my undergrad degree in Computer Science. At the time, there were only 2 other women in the program. This affected my studies greatly, as I experienced bias’ and discouragement throughout. I remember you for your desire to touch your students with your knowledge, and never second guess a student’s ability to succeed, in both class and career. It appeared to never cross your mind to neglect or pass over a single student. I hope you realize how invaluable this was to me. You are my favorite, most inspiring professor, even though I didn’t fully realize it until I came across the latest newsletter. Congrats on your Retirement! You certainly deserve it! Thank you, Amanda Stiles
July 7, 2014 Kelley Shaw Graduated: 1984
Hi Don, When I saw your picture in the CSE newsletter, it really brought back some memories! I honestly don't recall if I ever took any classes from you, but I remember you well. I worked in the "Microcomputer Lab" under Susan Rulon's direction. I worked in the Lab for two years (1980-81). I remember you helping set up the Lab and providing guidance to the Lab workers. The main thing I remember about you was your smile and your positive attitude. I am so glad to see that you had a long, successful career! Enjoy your retirement, Kelley Shaw
July 7, 2014 Clay Spinuzzi Graduated: 1991 Courses taken: 4410 and 4420
I was a CS major at UNT from 1988-1991. I honestly don’t remember much about the other CS profs (except for you and Dana Wyatt). But I remember your classes really well: I took (and really enjoyed) at least three classes from you, including the software development sequence. It was there that I really started to think about the architecture of large projects. I think that’s also about the time I started reading C reference manuals for fun and pushing myself to learn other languages such as LISP. Although I didn’t stick with CS, I applied the lessons I’d learned to other large-scale projects. It turns out that the basics of good coding are also the basics of good technical documentation and good research design. I still use those basics every day. Thanks again — you did great work at UNT, and I’m really blessed to have been able to take your classes. CS
June 30, 2014 Chris Kee Graduated: 2013 Courses taken: 3420 and 4410
I really enjoyed the 2 courses I took by you! I was inspired and challenged by your teaching and now after graduating I enjoy my new career as a web programmer. Glad to have had you as a professor! Enjoy your time off of teaching! - Chris
June 30, 2014 Mo Elzubeir Graduated: 2002 Courses taken: 4410 4420
It was my great pleasure to have been in your classes and I look forward to seeing you publish books in the near future! I often look back and appreciate the "just go out and get it done and if you're stuck come in and ask" style you had. Thank you for everything.