Officials overseeing the Dulles Toll Road and the Dulles Rail project swarmed a McLean elementary school Thursday night in the last of three sessions designed to educate residents on the rising costs of travelling the toll road and to get feedback.

Fourteen Metropolitan Washington Airports Authority, or MWAA, staff members were on hand to point to large charts and explain the rail project’s financing to the handful of residents who trickled through, many of whom weren’t happy about the likely prospect of tolls rising to $2.75 in 2013, $3.50 in 2014 and $4.50 in 2015.