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Geoffrey D. Decker, BA, MS

Northern Illinois University

Department of Computer Science


General Announcements:

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

Spring 2020 Teaching Schedule:

CSCI 360-2 - Assembler Programming:  9:00-9:50 AM on MWF in PM 251
CSCI 360-0PE1 - Assembler Programming:  12:00-2:45 PM on Th at Harper College in Palatine, Illinois, in Building D, Room 278 (D-278)
    CSCI 428-1/524-00P1 - Advanced Android Mobile Device Programming:  2:00-3:15 PM on MW in Cole 106
    CSCI 465-1 - Enterprise Application Environments:  11:00-11:50 AM on MWF in PM 251

Spring 2020 Office Hours:

10:00-11:00 AM on MWF
    1:00-1:45 PM on MW
    10:00 AM-12:00 PM on Th in D-264 at Harper College

    and 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 and D-264 at Harper College
             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 the Missouri River bluff town of Atchison, Kansas (Amelia Earhart, the famous aviatrix, was born there too!), to a family with three older sisters.  I grew up in the Kansas City area on the Kansas side in the 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 art 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 Drs. George Lawner and 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 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 record-keeping company for the mutual fund industry.  At Kemper and DST, I developed systems in COBOL, Assembler, 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 systems programming.
While at DST, I founded and conducted the DST Symphony Orchestra and the DST Wind Ensemble, both made up of DST employees, their families and friends.  I was soon invited to conduct the DST Wind Ensemble and members of the Kansas City Symphony in an outdoor concert inaugurating Kansas City's Avenue of the Arts.

In 2001, I decided it was time for a change and began my career as an instructor 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 working with many talented students.  I was awarded the Department of Computer Science's Excellence in Teaching Award in both 2005 and 2019, an honor I appreciate very much.  With the Spring 2020 semester, I continue my 19th year and begin my 56th semester teaching at NIU.  I love teaching!  It's the best job in the world!

Finally, I regularly play French horn in both the Kishwaukee Symphony Orchestra and the DeKalb Municipal Band.  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 review classical CDs and downloadable music files for various publications. 

Concerts in which I'm involved during the 2019-2020 concert season:

    Visit DeKalb Municipal Band Concerts soon for information about the summer 2020 season.
    Visit Kishwaukee Symphony Orchestra for more information about the 2019-2020 season.