You can look something up on wikipedia, then be told by the teacher that Wikipedia is not a primary source when you try and cite it. So you look at Wikipedia's

You can look something up on wikipedia, then be told by the teacher that Wikipedia is not a primary source when you try and cite it. So you look at Wikipedia's citations, and find they're paywalled. The internet is conducive to learning; it's not conducive to our educational establishment's hoops.