Life-shaping influence

Hi~, In the following phrase underlined, whose life is influenced? Johnson, the one who became a public school teacher? Or the children who could be his students? What do you think? Thanks~

After the life-shaping influence of being a public school teacher at the start of his career, Johnson built and left an immense educational legacy in the early childhood education reforms of Operation Head Start and in the
Elementary and Secondary Education Act that assigned federal resources to offset local inequities.