A lady at Radio Bremen tells me that their online Plattdeutsch course will begin on September 29th.
Here is a link to it:
http://www.radiobremen.de/wissen/dossiers/plattdeutschkurs/intro100.html
The page is not ready yet,but you can save the link,and start using it on the 29th.
Just in case anyone is interested...

thanks, my niece is learning deutsch

Keep in mind that Plattdeutsch is very different from standard German. So your niece might consider it interesting, but if she learns standard German she better sticks to it, as Plattdeutsch is not a standard in the German-speaking world. In fact, there are several variations of Plattdeutsch.

Yes,this is a North German language.
It didn't participate in some of the sound shifts that the Hochdeutsch varieties did.
This also isn't going to be that Mennonite Low German.It should be the local lingo used around the Bremen and Hamburg areas.
I agree with Purolator.
Hochdeutsch is best to learn first,as it will be more useful.
Unless your life's goal is to be a farmer in Schleswig-Holstein,or work in the shipyards in Hamburg or Kiel.