Primary pupils who protested outside Camden Town Hall over plans for a luxury home next to their playground were celebrating this week after the scheme was thrown out by a government planning inspector.

Children and staff at St Christopher’s School in Lyndhurst Gardens, Belsize Park, were told the news on Monday.

Developer Lyndhurst Gardens LLP had appealed to the planning inspectorate after Camden Council turned down the application following the pupils’ protest at the town hall in September.

Their campaign had the backing of celebrity parents Damian Lewis, from hit TV series Homeland, and wife Helen McCrory, who starred in the Harry Potter films.

School bursar Caroline Korniczky said: “We are absolutely over the moon. It’s the right decision and it’s just fantastic news.”

The school feared the three-bedroom house would tower over its science garden, little more than a metre from the site, and render it unusable due to dust and noise.

The plans, which would have seen a 1970s bungalow demolished, included a two-storey basement excavation and a swimming pool, gym and sunken courtyard.

Cllr Chris Knight, Conservative ward member for Hampstead Town, said: “It’s tremendously good news. It will send a message to developers that they can’t just walk in here and do what they want.

“The simply fact is the plan was not suitable for the site. It was a really awful looking thing and it had all the charm of a World War Two bunker.”

The developer declined to comment.