You will find elsewhere on this Web site descriptions for several sun and atmosphere monitoring instruments developed for use by students. These are essentially research instruments that aren't available commercially. Although they are not complicated, and they are relatively inexpensive in terms of hardware cost, the expense of their calibration and interpretation precludes their production as commercial "off the shelf" instruments for use by GLOBE or similar programs.
It is possible in some cases for students to build their own sun and air monitoring instruments. Completed instruments need to be calibrated, in cooperation with GLOBE or other scientists, so they can be used to collect valid data that meets GLOBE and other science standards. Some basic electronic construction skills are required. Unfortunately, it is increasingly rare to find teachers and other adults with these kinds of skills. Still, dozens of GLOBE sun photometer kits have been purchased by schools and individuals during the last few years. This is a worthwhile activity that is well within the capabilities of middle and high school students under appropriate adult supervision. When students build their own instruments, it greatly enhances their sense of ownership of the data collected from those instruments.