Nominated Member of Parliament Wilson Sossion intends to table a Bill in Parliament to limit the number of learners in a classroom to between 25 and 35.
Mr Sossion, who doubles up as the Kenya National Union of Teachers (Knut) secretary-general, said most classrooms were "overpopulated", diluting the quality of learning.
Addressing principals from Baringo County at the end of a three-day workshop in Naivasha at the weekend, he said the move would ensure an improved learning atmosphere.
"We have in some instance close to 70 learners in a classroom, greatly compromising the quality of learning," he said.
He said there were more than 292,000 unemployed teachers, against a shortage of 104,821.
Mr Sossion said limiting the number of learners per classroom would greatly improve the quality of learning, especially in primary school.
He praised the government's decision to hire 88,000 teachers after MPs approved a Sh26 billion recruitment request, pending approval by the Treasury.
But he maintained the number was still not enough to address understaffing in most public institutions.
He vowed to remain a nominated MP despite a recent ultimatum by the union's top decision-making organ, the National Executive Council, that he decide between serving teachers and retaining his parliamentary seat.