When observing the effectiveness of a distance learning program, what factors do you consider for evaluation?

"I have experienced this over the last two years when my own classroom went virtual. For one, I know it's critical to establish criteria for the students so they are clear on what they must know from one lesson to the next. I achieve this in a number of ways. Sometimes through direct interaction with the students. Sometimes I do so via written assignments or tests. Another key to evaluating the effectiveness is accessibility. In a classroom setting, student accessibility was less of a concern because students were literally present in the classroom. In the virtual world of education, I need to take into account the accessibility of mixed media like presentations and videos and audio lectures, as well as platforms and even connectivity. It's critical for all students to have access. Poor access has a direct impact on the quality of education."