Umm. I would be very hesitant to turn in a typical Arduino sketch for an "Object Oriented Programming" class. C++ may be an "object oriented language", but that just means that it has features that HELP a programmer write object-oriented code; it doesn't automatically make your program object-oriented. ("I can write a C program in C++, Java, or Perl...") Especially given that many things stressed in OOP (inheritance, dynamic allocation, I dunno) rarely appear in the user portions of an Arduino sketch...