outsider:
You have a short circuit from 5V to pin 8, that will burn out pin 8 if it goes low.
And where did that program come from? Why didn't you use one of the library examples?
Here's some datasheet links that might help, good luck.
http://robocraft.ru/files/datasheet/28BYJ-48.pdf
http://www.ti.com/lit/ds/symlink/uln2803a.pdf
Thank you for taking the time to try to help. I removed the short (a clumsy addition born of desperation after several rewirings), but I'm afraid it still doesn't work. I can feel the motor vibrating.
That program was an extension of a previous program that worked, with the previous code omitted (all it did was read a potentiometer and display a pattern of blinking LEDs). I used library examples as a basis, as well as several online examples that were very similar. I haven't been able to connect a single combination that works.
I read through both of the links that you gave me- the TI link had details that were over my head and beyond the scope of the course that I'm taking. The details that I did understand unfortunately didn't result in a rotating motor.
If you'd like to take a second crack at what I'm doing wrong, I'd greatly appreciate it, but I understand if you don't. Thanks again.