I would find out what the student is passionate about and then use those interests as natural motivators to increase engagement. Every student learns differently. I think differentiated instruction will assist students who are having difficulties understanding complex concepts. What techniques would you use to be sure that a student understands the material? I would ask students to paraphrase information. Paraphrasing is a powerful tool that helps students assimilate and rethink information. It turns them into active learners, and it helps me check to see if the student genuinely understands the material. In the past I have also used what is known as a misconception test, in which I present students with common or predictable misconceptions about the concept that I am covering and then ask them whether they agree or disagree and to explain why.