The cash injection, to be released over two years, comes from the Act for Change Fund - a partnership between two foundations and a government-backed initiative.
Among six groups to receive £100,0000 is West Midlands-based Beatfreeks, which will fund its React project helping young people use art to campaign about issues in their communities.
Another recipient is advice and counselling network Youth Access, which will use the money to link up young people to mental health leaders and policymakers.
Northern Ireland Youth Forum, which helps disadvantaged young people in Belfast, will use its grant to fund a youth worker and studio space to get service users involved in local and national issues.
Youth leadership organisation UpRising will spend the money to employ a campaigns and engagement officer to help to develop students' social action.
The Advocacy Academy, which runs a social justice course for young people, will use its grant to bolster its senior management with the appointment of a programme director.
Hull-based counselling and advice service The Warren will employ a youth "empowerment support worker" and a digital media campaign facilitator, as well as resources for marketing, film-making, workshops, publishing and mental health support.
Legal rights group Just for Kids Law has received an £87,000 grant to fund a youth engagement officer post to help young people who have been excluded from school to campaign around the educational, emotional and psychological impact of school exclusion.
This is the first round of funding of a total £3.6m earmarked for supporting youth engagement.
"We believe young people play a critical role in delivering social change," said Paul Hamlyn Foundation trustee Jan McKenley-Simpson.
"By prioritising support for those with experience of disadvantage, the Act for Change Fund aims to create a more diverse group of social, cultural and political leaders for the future."
The Act for Change Fund is a partnership involving the Paul Hamlyn Foundation, Esmee Fairbairn Foundation and the government-backed #iwill Fund.