Google Sites is great with it's connection to Google Docs, but has a sizeable learning curve.
Community Review for Google Sites
My Take
Google sites has MANY uses and makes a great companion to other Google Drive Apps. It makes a good portfolio tool for those schools who have a Google Apps Domain, because your students can use the same account. It isn't the easiest Google tool to learn and doesn't feel intuitive. The teacher must do the most, if not all the work for younger students.
How I Use It
While we are starting to use it as a staff professional development content tool, our main use is as a student portfolio tool. Students create a Google Site starting in Kindergarten (or Transitional Kindergarten) that includes exemplar work and reflections through the year. Students add to the portfolio each year and end up with an evidence record of their learning and growth.