This is a very complex question. For starters, the expectations depend on the situation or desired outcome. For example, educators have academic, behavioral, socio- emotional and sometimes, physical expectations of their students. For a student, the expectations can be markedly different. Students may desire social outcomes over behavioral of academic outcomes. If this is the case, they may expect to make new friends rather than do their studies. So, in an effort to conceptualize this question, I am going to answer it from the perspective of an educator, and touch on a few areas that I've referenced above.
Literacy is a challenge for many schools, and particularly for the students they teach. With that in mind, it is likely that an educator will expect his/her students to complete daily reading and writing entries. A general rule of thumb is 15 minutes of reading for every 3 grade levels. Thus, a 6th grade student should be able to read for 30 minutes daily.
Another plausible academic expectation is that students will have a planner, or something to keep track of homework assignments and tasks. Educators may require students to write in their planners, and offer a participation grade for the active use of one. This is, after all, a basic study skill.
When I taught K- 12 grade students, I would begin the first week by setting expectations for our class together. It was at this time that I could learn what was most important to my students, and give them a voice and ownership over our learning environment. Most commonly, I could steer in some valuable citizenship expectations like not talking when someone else is speaking, or being respectful of everyone's time and property. However an educator chooses to do this, it is a good rule of thumb to limit class expectations to a top 5, and explicitly discuss how each expectation does, and does not look.
Parents want to know about these expectations, too. For that reason, I never sent a syllabus home on day 1. I would always wait until the class chose their expectations, and then I would send a syllabus home by the end of the week. It was an expectation that the syllbus acknowledgment pages were signed, and returned.
As more and more technology is being brought to the classroom and other learning environments, it is increasingly important to discuss what good, ethical, and responsible online behaviors are. Often times, this gets into the cyber bullying conversations, and means laying ground rules for how tech will be used in the class. Before addressing this topic, however, sit down and reflect on your views and comfort levels as an educator. Once you know what you will accept and reject, you can help the students to better understand those things, too.
Regardless of what expectations are ultimately chosen and disseminated, remember to inspect what you expect. An expectation does no good if it is never monitored, followed up upon, and/or explained.