I use the evaluating sources presentation toward the start of my sophomores’ research unit – we research careers, so our primary source is the Occupational Outlook Handbook (found online), and then I ask students to find one more source (at minimum) on their own. This presentation basically goes over the source evaluation worksheet that I have students fill out for each of their sources used for their career research.
I use the MLA format presentation (or these separate mini-lesson presentations) with my sophomores after we’ve completed initial research on careers, but before they’ve done any work on their essays. I have found that sometimes, it’s too much information at once, so using the mini-lessons works well if they would be overwhelmed by all aspects of the presentation. If they’ve done work with MLA format and citing sources before, the mini-lessons can work well as a quick review also.