She said: “We were promised by TfL that the frequency of the 533 bus from Hammermsith would be increased, but it has not happened. This is a disaster.”
The private school is paying for four extra coaches to be put on each day to pick up pupils from Hammersmith, Chiswick, Kensington and Fulham.
The bridge was first closed to traffic in April 2019 when cracks were discovered. It was shut to pedestrians, cyclists and river traffic in August.
Hammersmith & Fulham council, which owns the bridge, says it will cost £141 million to complete a full repair but £46 million to be able to reopen it safely to pedestrians.
The local authority and Transport for London say they do not have the money available.
The Government last week stepped in to set up a taskforce under Baroness Vere to find solutions.