My subject matter is statistics and mathematics. Biology students wind the material particularly challenging but it is fundamental to their future. The classes are very large and I have between 300-400 students split across multiple runs of the same lecture course. Without having the right tools to analyse the world around you, you are easily deceived. The tools are not hard to learn but they are usually presented badly. Those with a Maths background find it very hard to relate to students who cannot understand it at the same level. Lectures make this worse as they present large amounts of information and describe methods without putting them into context or letting the students experience the sort of real problems and real data they will see when they are doing their projects or in the future when they are working.
There is a more fundamental problem, in that we are not always giving students what they need when we teach them. There are too many facts when with the Internet rote memory is less important than application. Our existing assessments also fall into this trap by not assessing in a way that encourages deep learning and acquiring the knowledge for life, rather than for the exam. I had one graduate level student who has attended a statistics courses six months before. The course had been given good feedback and the students were very sure they had learned statistics. But after 6 months the student could not carry out the most basic statistical analysis using software tools!
The ways I think online learning can help are:
Reducing the amount of times the material has to be delivered.
Building the confidence of the students by having more significant interactions.
Encourage deeper learning.
Promoting group work and the sharing of experiences.
Allowing the use of more case-study based work to put the subject into context.
Changing the way assessment can be done by combining online assessment with continuous assessment.