Teachers at a Sussex school in the middle of a battle over plans to turn it into an academy are due to go on strike today.
Hove Park is closed to students, with a picket line expected at its entrance from 7am this morning.
Campaigners want to stop the school being converted into an academy, which would bring it out of local authority control.
ITV Meridian spoke to parent Natasha Steel.
David Cameron believes disruption caused by today's public sector strikes is "wrong", his official spokesman said.
Asked whether the Prime Minister felt strikes in the public sector could ever be justified, the spokesman said: "Does the Prime Minister think that people in this country - parents, commuters, users of public services - should have their routines disrupted? Of course he doesn't think it is right."
Asked for the PM's assessment of the impact of today's strikes, the spokesman responded that Cameron would say "any disruption any user of public services experiences is wrong".
Public sector workers in the Isle of Wight have joined protestors across the Meridian region who are unhappy about their pay and working conditions.
Phil Hornby with Labour candidate in Brighton Pavilion Purna Sen, Rehman Chishti the Conservative MP for Gillingham and Rainham, and Jackie Porter the Lib Dem candidate in Winchester. With a guest appearance by the irrepressible Baroness Trumpington
Cabinet Office Minister Francis Maude said fewer than 20% of civil servants were on strike today compared with a third in the last big walkout in 2011.
Mr Maude said today's disruption was the fault of union leaders and urged public sector workers that the right to strike must be exercised "responsibly".
He pointed out that only one in five members of Unite and Unison had taken part in ballots leading to the strike, adding that low turnouts strengthened the case for reform.