prova semplicemente così: http://jsbin.com/ekusez/1/


codice:
.board {
   width: 400px; 
   height: 304px;
   line-height: 304px;
  
   white-space: nowrap;  
}

.board div {
   display: inline-block;
   vertical-align: top;
   height: 150px;
   width: 100px;
   border: 1px #c8c8cf solid;
   white-space: normal;  
   line-height: normal;
}

.board div:nth-child(2n) {
   vertical-align: bottom;  
}