Personal is to handle an advertising push by the School Food Trust to promote healthy eating in schools.
The agency won the business following a four-way pitch and has created an integrated campaign around the theme "Eat Better, Do Better".
The School Food Trust, which had no agency previously, was set up in 2005 to improve the quality of food served in schools in the wake of celebrity chef Jamie Oliver’s high-profile School Dinners television series.
The Government pledged more than £200m to improve school dinners after Oliver’s campaign against food such as turkey twizzlers.
An initial campaign breaks next week, but more activity is likely to follow later in the year. It will be aimed at everyone from teachers and school governors to parents and children.
Personal, which was set up in 2004 and is part of Engine Group, has developed targeted above-the-line advertising and direct marketing to change attitudes and perceptions of school meals.
The agency’s managing partner Chris Ward says: "The taste and nutritional value of school meals is clearly a high-profile issue."