Check out products related to Geography, Travel and the Outdoors on Amazon:
www.amazon.com/shop/darrongedgesgeographychannel (Paid Link)
Sand dunes form when wind erodes and transports sediment up a beach and deposits them on an obstacle like like driftwood or vegetation. The sand can be transported by the processes of saltation, suspension and surface creep. This video covers: (1) How sand dunes form. (2) The environmental conditions that must be present for sand dunes to form.