School Mural under way....

 Yesterday I started to put together this year's school mural. I got to square 151, out of 300. It will take about 10 hours total to complete. This is always an exciting and exhausting process. Wonder what this mural is a painting of? Hint: A teacher stopped by while I was working and I gave her this clue: "The bottom half of this very famous painting is not nearly as recognizable as the top half."