Why did the Board of Education Spend $9,773 at the BWI Hilton in 1 Week Last Summer?

The Parents' Coalition has obtained Board of Education expense account records for calendar year 2017 through March 15, 2018.

Included in the documents we received are copies of the Board of Education's JP Morgan Chase credit card bills.

The July 31, 2017, Board of Education credit card bill shows three charges under the category of Travel activity from "Hilton Baltimore BWI" on three days in July with arrival dates of July 4, July 9 and July 11.   The total for these three transactions is $9,773.19.

What were these credit card transactions for?