While this may seem like the role of a webmaster to ensure links on webpages are working, it is very important students understand that when they are posting content to the internet, their links must be current and working.
The best way to approach this when teaching is to demonstrate Link Checker: https://validator.w3.org/checklink.
Ask the student to go to their station website, find a page with links and pop it into Linkchecker.
This online program will show you any broken links so they can notify the person who looks after the station website that they need to be fixed.
In terms of the assessment, they just need to make sure any links they embed in their blog posts actually work, so they must go back and click on them a week later and make sure they are still active and fix any that are broken, the easiest way for them to check is to pop their blog page into Linkchecker!