Web2PDF Online is a free service that will convert HTML to PDF for your websites so your visitors can quickly save information on your site to a PDF file. It also keeps track of all of the PDF conversion activities on your site.
The site offers support and it is really easy to use.
This could be a good option if you would like people to be able to save parts of your blog or website as a PDF file, including having students do it as an archive of material for their notes.
Lots of PDF resources - print, markup, convert and more