This was a project we did in the 2009/2010 school year. A couple of mosaics were auctioned off and three are hanging in the Elementary schools. There is one located at the Miller entrance and another located in the Placentino office hallway. The final one is located in the Placentino Library.
I was able to take a weekend class in mosaic art courtesy of the Holliston Education Foundation. The Instructor of the course was well versed in mosaics and has several installations in the New England area. She has also created mosaics with elementary school students and was able to pass on several insights.
In addition to our weekly curriculum, students in Miller and Placentino will be participating in designing and assembling the mosaic. 
The Blog:
http://mosaicholliston.blogspot.com