Using Electromagnetic Radiation to Understand the Sun

What's the Sun Doing Lately     http://www.lmsal.com/YPOP/Spotlight/Today/
From the Yohkoh Mission Public Outreach Page:  Information about and views of the sun in different wavelengths of light.

Do You See What I See?   http://www.lmsal.com/YPOP/Classroom/Lessons/Filters/
From the Yohkoh Mission Public Outreach Page:  A lesson about astronomical imaging using different color filters.

The Sun, A Pictorial Introduction     http://www.hao.ucar.edu/public/education/slides/slides.html
From the High Altitude Observatory,  (http://www.hao.ucar.edu/) a division of the National Center for Atmospheric Research.  This collection of slides serves as an excellent introduction to the study of the sun, however the text is written at a college level.  Here is an easy lesson with which you can adapt the slide show for a middle or high school classroom.