Q. I want a pdf of the article from Journal of the Learning Sciences Flowing toward correct contributions during groups' mathematics problem

We don't have online access to that issue of the journal.  However, if you have set up an interlibrary loan account, you can request the article through the screen with the "We were unable to find any links" message.  A working link can often be e-mailed to you within a few days.  If you haven't set up an ILL account, you can do so using a link near the middle of the library home page (http://library.unomaha.edu).