"Nobody expects to come top," said the head of Sherington primary in Greenwich. "Everybody is very pleased."
She joined the school three years ago along with eight other members of staff.
"I've been lucky and managed to recruit and retain a really good team of teachers who work too many hours. It's good for the children, but not necessarily for staff. From time to time I have to tell them to go home."
In 2001 the school's key stage 2 aggregate score was 103. It rose to 204 in 2002, 239 in 2003 and this year's score was 254, giving it an increase of 151 points.
Ms Atkinson said: "There were places at the school three years ago, but they have been filled now.
"As the reputation of a school improves, spaces become filled.
"This is a typical London school. It hasn't been easy, but no school is easy. There are 22 languages spoken here. We have a broad intake that varies between children from middle-class families and those from refuge accommodation.
"The teachers here are really committed and deserve the recognition that this league-table position gives them."