Student relevence is critical. If the material is relevant the learning can come about in a variety of ways.
Case and point. I am a 26-year-old man. Of course, it is my inclination that to broaden my German knowledge, I will check out Deutche Welle's website for easy articles on German and international current event stories. Articles even come equipped with keyword glossaries pre-defined.
The problem is, despite loving news and politics, there is very little retention. My current vocabularly is simply too small. The same story in English can be glanced through, absorbed quickly, even if the topic is only slightly appealing. I can then pass onto something more fulfilling. In German, my investment needs to be 100%, even if my interest has already petered out from both loss of interest and the friction of a rough language barrier.
However, if I watch German chldren show sensation Die Sendung mit der Maus, I feel way more engaged. I will admit as a 26-year-old man, that I do not know the ins and outs of a crime scene investigation. Nor did I realize what went into the storage of religious gold statues in a cathedral. Yet, these topics are fascinatingly captured on this kids show, and the vocabulary derived from this Sesame Street-like is having much greater staying power. Sure, it is maybe a tad easier, but the language is still fast and at time colloquial. The difference is my interest.
So my pro tip is to find something that appeals to you. Now I am off to play Final Fantasy IV in German.