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Decker Photo

Geoffrey D. Decker, B.A., M.S.

Northern Illinois University

Department of Computer Science


General Announcements:

     Be sure to check Blackboard Academic Suite at for your class and section!

Fall 2021 Face-to-Face and Online Teaching Schedule:

CSCI 322/522 - Android Mobile Device Programming:  10:00 AM-11:15 AM on MW in Cole 106.
CSCI 360-2 - Assembler Language Programming:  1:00-1:50 PM on MWF in PM 203.

CSCI 465-1/465-PE1 - Enterprise Application Environments:  2:00-3:15 PM on MW in PM 203 for Section 1
                                                                                                             and concurrently online for Section PE1.


Fall 2021 Online Office Hours:

Online at 9:00-10:00 AM on MW, 12:00-1:00 PM on MWF and also by email and appointment.

Contact Information:

       Campus Address:

               Geoffrey D. Decker, BA, MS
             Northern Illinois University
             Department of Computer Science
             DeKalb, IL  60115-2854 

       Office Information:

             Office:  PM 463
             Department Phone:  815.753.0378


   Huskie   M.S. in Computer Science        Northern Illinois University        DeKalb, Illinois

   Jayhawk    B.A. in Music                            University of Kansas                    Lawrence, Kansas

About Me:

I was born in Atchison, Kansas (Amelia Earhart, the famous aviatrix, was born there too!), to a family with three older sisters.  I grew up near Kansas City, Missouri, in the Kansas suburbs of Mission, Prairie Village, and Overland Park.  My father, Kenneth Decker (1916-1994), was a barber by trade and my mother, Beverly Dege Decker (1925-2002), when she worked outside the home, did graphic design and artwork for a large yearbook publishing company.

I graduated from Shawnee Mission South High School in Overland Park, Kansas, and attended the University of Kansas in Lawrence, Kansas, where I completed a B.A. in Music with an emphasis in Music History.  Throughout my time at KU, I played horn in the university's marching band, symphonic band, and symphony orchestra.  I also played as a member of the local musicians' union in the semi-professional Lawrence Chamber Players, Topeka Symphony Orchestra, and Lawrence Symphony Orchestra.  Besides playing, I studied some orchestral conducting with the late Dr. George Lawner and Dr. Zuohuang Chen and horn with Professor David Bushouse.  

After graduating from KU, I worked in various jobs for a few years and eventually moved to DeKalb, Illinois, to begin the M.S. in Computer Science degree program at Northern Illinois University.  It was an eye-opening experience and difficult but I found a niche in developing software and systems -- and eventually in teaching it -- that I enjoy very much.

After graduating from NIU, I worked 11 years as a software developer in Kansas City, Missouri, at both Kemper Service Company, the transfer agency for Kemper Mutual Funds, and DST Systems, Inc., a former record-keeping company for the mutual fund industry.  At Kemper and DST, I developed software in COBOL, Assembler language, C, C++ and CA-IDEAL, and spent two years as an upper-level technical recruiter in DST's Employment Department.  My final two years at DST were spent in mainframe system programming.
While at DST, I founded and was the conductor of the DST Symphony Orchestra and the DST Wind Ensemble, both made up of DST Systems employees, their families and friends.  In summer 2000, I was invited to conduct the DST Wind Ensemble I drew from my DST Symphony Orchestra along with members of the Kansas City Symphony in an outdoor concert inaugurating Kansas City's Avenue of the Arts.  It was a great success!

In 2001, I was ready for a new adventure and moved back to Illinois to begin my career teaching Computer Science at Northern Illinois University.  I had taught courses in COBOL, Systems Analysis and Design, Music Appreciation, and the humanities at National American University in Kansas City, Missouri, but wanted to teach full time.  Northern Illinois University's Department of Computer Science provides me that opportunity, and I am very happy to be here.  I have been awarded the Department of Computer Science Student Advisory Board's Excellence in Teaching Award for academic years 2004-2005, 2018-2019 and 2020-2021, honors I appreciate very much.  With the end of the summer session 2021, I finished my 20th year at NIU.  With the fall semester  2021, I begin my 21st year and my 60th consecutive semester teaching at NIU.  I love teaching!  It's absolutely the best job in the world!

Finally, I regularly play French horn in both the Kishwaukee Symphony Orchestra and the DeKalb Municipal Band and serve as a member of the Executive Board of the Kishwaukee Symphony Orchestra.  I also write the program notes for the Kishwaukee Symphony’s concert programs.  As often as I can, I act as an IT consultant, and I write classical music articles and review classical CDs and downloadable music files for various publications. 

Concerts in which I'm involved during the 2021-2022 concert season:

    Visit DeKalb Municipal Band Concerts for more information about the band's 168th consecutive summer season in 2022 at Hopkins Park's Dee Palmer Band Shell in DeKalb, Illinois.
    Visit Kishwaukee Symphony Orchestra for more information about the 2021-2022 season.