As teachers we all want to reach each student we teach. Differentiation strategies must be in place in all classrooms for our students to be successful. In an online setting differentiation can include choices of videos, links to websites that show lessons being taught, interactive or webquests options, and textbook pages to read. I found an interesting video on differentiating in the math classroom. It is quite long, but has great ideas.
A video dedicated to learning algebra (which is also long but resourceful)