It can be contrasted with scanning, which is reading in order to find specific information, e.g. figures or names.
Example
A learner taking a reading exam decides to approach text by looking at the title, introductions, and any diagrams and sub-headings, then skim reading to get a clear general idea of what the text is about.
In the classroom
Skimming is a specific reading skill which is common in reading newspapers, messages and e-mails. It is important that learners understand that there is no need to read every word when skimming, so often teachers set this as a timed task to encourage speed.
See also:
https://www.teachingenglish.org.uk/article/scanning
Further links:
https://www.teachingenglish.org.uk/article/theories-reading-2
https://www.teachingenglish.org.uk/article/unit-4-reading-skills
https://www.teachingenglish.org.uk/article/making-reading-communicative
https://www.teachingenglish.org.uk/article/activities-using-magazines-classroom
I shall use this idea of Timed task to skim through the text. This will help the level one and level two readers comprehend quickly by making connections with the title and the images.