This project was done as classwork for
Independent University Bangladesh
CSC 470: Introduction to Parallel Programming.
In this step by step tutorial we shall learn how to setup a couple of Raspberry Pi's to create a small cluster.
It will discuss the hardware details, the process, basic OpenMP and Parallel how to connect them and write a basic C++ program to make them work together. We assume you already have the C++ knowledge necessary to take it further. Hope it helps.
Link: (with download PDF)
http://libregarage.com/tutorials/raspi_openMP.html