Sand in our Shoes

Aubrey has a sandbox at preschool.  We have been at this preschool for 4 years now... Taylor for 2 years and Aubrey for 2 years...  I have had sand dumped on my floor several times a week for 4 years while my girls attended this preschool.  It was pretty bad when Taylor was in preschool, but Aubrey... now Aubrey is a different story.  Aubrey comes home with rocks, sticks and sand in her shoes.  I have NO idea how she manages to walk around for the rest of the day with this stuff in her shoes.  I snapped a picture because soon I won't be sweeping up sand... sniff, sniff....  This was a mild day for her as it was just sand ... no sticks, etc...