Dr Paul Mortimer is a key adviser to the Department for Education and Skills' innovation unit and has already led the way in other radical changes to schools, including using cover supervisors to take lessons.
He plans to rebuild Hollingworth high in Rochdale, one of the two schools where he is an executive head, by 2008 so it can teach students all year round. Costs will be met by the Government's Building Schools for the Future scheme.
Teachers and the 1,200 pupils would still attend 190 days a year, the national standard. But pupils would be in eight mixed-year groups so their terms and holidays would fall at different times.
Poorer families would be offered term-times that would let them take holidays in cheaper off-peak periods. Teachers would also be able to book holidays that coincided with their children's, even if they were in other authorities.
Because the school would have fewer pupils on site at any time, it will be rebuilt to two-thirds its existing size.
Dr Mortimer said: "For the first year the school would have the normal Monday to Friday working week, but a year after that we would start lessons on Saturdays and a year after that on Sundays."
Heads' associations said the idea was feasible and fitted with the drive for extended schools. But the National Union of Teachers said it was impractical and teachers would be angry to lose traditional holidays and weekends.