Go to your Media Center and see what types of texts there are available in the resource section on any of the nine planets, Europa, and any other body that you may want them to create a brochure for.

I have searched the various sites and am posting them to aid you in finding appropriate materials for your student's to use as research.

This site includes information about all nine planets, the moons, etc...  It also has mini-videos on the formation of the solar system and Europa's rotation.  This is an excellent resource.
http://www.solarviews.com/eng/homepage.html

The following sites contain information on the nine planets and various other celestial bodies.
http://seds.lpl.arizona.edu/nineplanets/nineplanets/nineplanets.html
http://www.nineplanets.org/overview.html
http://wwwflag.wr.usgs.gov/USGSFlag/Space/wall/wall.html
http://www.geocities.com/CapeCanaveral/Lab/2683/index.html
http://www.stemnet.nf.ca/CITE/solar_activity.htm#Formation
http://starchild.gsfc.nasa.gov/docs/StarChild/StarChild.html

The following sites contain excellent photographs for use in brochures.
http://pds.jpl.nasa.gov/planets/welcome.htm
http://www.the-solar-system.net/

Some of this site is a little elementary, however it is adaptable.
http://www.abcteach.com/SolarSystem/SolarSystemTOC.htm