When it was built in c. 1889, the Walter Lenox Elementary School served the white community and was a vocational school between 1914 to 1931. The school was named after Walter Lenox, a Yale-educated attorney who was mayor of Washington, D.C. from 1850 to 1852. While in office, he was known for giving great attention to the public school system. The school was converted to 14 pet-friendly condos in 2004.
I found a listing for a penthouse loft; the asking price is $799,000 for 2 bedrooms, 2 baths and 1,325 square feet. Some pictures of the interior are located at http://www.sellingdc.com/listing/dc10162062-725-5th-st-se-31-washington-dc-20003/
Car Barn, remnants of the past, posted earlier: