Journal for Research in Mathematics (Full text until 2003)
Mathematics Teaching (All full text)
The Mathematics Teacher (Full text 1992-1995)
Opposing Viewpoints - Direct link to search only statistical data.
Reading in the Mathematics Classroom - A chapter from the ASCD book, Literacy Stragies for the Mathematics Classroom.
Below is a sampling of widgets found on the Wolfram Alpha website. They're easy to make and over 2000 math related widgets available!
Find more here: Wolfram Alpha Math Widgets