He completed his primary school education at the Lethabong Primary School in Wallmansthal, near Pretoria, and proceeded to Wallmansthal Secondary School from 1965 to 1967 where he obtained his Junior Certificate with distinction. He matriculated at Hebron Training Institute in 1969. In 1970, he enrolled at the University of Zululand (Ngoye) for a BSc degree. Whilst at Ngoye, he was elected to the SRC, and became active in the programmes of the South African Students’ Organisation (SASO). He discontinued his studies and moved back to Pretoria where he became active in the local branch of SASO, PRESO.
In December 1972, he was elected be the first National Organiser of the Black People’s Convention at its inaugural Congress. In 1973, he was detained under the notorious Section 6 of the Terrorism Act in Port Elizabeth. He was later charged, convicted and sent to Robben Island for five years. He was the first Black Consciousness activist to land on Robben Island. While on Robben Island and under banning orders, he completed a BSc and BSc Hons degrees with the University of South Africa(UNISA). He now holds a Master of Science degree in Applied Mathematics from UNISA.
On his release in 1978, he was banned and restricted to Mahwelereng Township in the then Lebowa Homeland (now part of the Limpopo Province) for five years. In 1981 he went into exile, and joined the Black Consciousness Movement of Azania (BCMA). He was first elected Chairperson of the Botswana Chapter of the movement, and in 1982, Chairperson of the Central Committee of the entire organization. In 1983, he moved his operational base to Zimbabwe, where he resided until he returned to South Africa in July 1994. On his return from exile in 1994, he was elected President of AZAPO at the merger Congress of the BCMA and AZAPO.
He was elected a Member of Parliament in April, 1999, and appointed the Deputy Minister of Education in January 2001. His main responsibility in this post was Maths and Science education, and to that end, he launched the Dinaledi schools.
In April 2004, he was appointed the first Minister of Science and Technology. In this portfolio he presided, inter alia, over:
- the expansion of relations between the South African science and technology system with those of other countries across the globe
- the commissioning and building of the South African micro-satellite, the SumbandilaSat
- the support and funding of the development of the South African electric car, the Joule, by the then Innovation Fund, an instrument of the Department of Science and Technology
- the creation of the Technology Innovation Agency(TIA)
- the launch of the South African Research Chairs Initiative
- the winning and launching of the African component of the International Centre for Genetic Engineering and Biotechnology
- the development of the South African Ten Year Innovation Plan.
He also chaired the SADC ministers responsible for science and technology, and the continental African Ministers’ Council on Science and Technology.
He is the author of five books, viz., On Your Own (1989); A Quest for True Humanity (1996); A Twin World (1996), My Grandmother is Permanent (2004) and Let the Patriots Stand Up (2013)
He was the first patron of the Sowetan-Telkom Mathematics and Science Teacher of the Year Awards, and the founder Chairperson of the South African Literacy Initiative and Masifundesonke Reading Campaign.
On 18 March 2008, the Vaal University of Technology conferred upon him an Honorary Doctorate (Doctoris Technologiae) in the field of Applied Sciences in recognition of his “service and invaluable contribution to the social upliftment of both our region and country.”
On 11 December 2009 the University of Stellenbosch conferred upon him an honorary Doctor of Science degree and made this observation about him:
“… Mangena has achieved exceptional merit and given proof of eminent gifts of intellect and character,…for his contribution to strengthening science for society; for his successful efforts towards increasing national spending on research and development, and for his outstanding contributions to the development of human capacity in South Africa”
On 30 March 2010, he was appointed a member of the Human Resource Development Council, a body chaired by the Deputy President of the Republic of South Africa.
On the 4th August 2010, he became a board member of the Mapungubwe Institute For Strategic Reflection.
On the 26th February 2011, he was appointed to the board of the MTN SA Foundation.
He became a Fellow of the Stellenbosch Institute for Advanced studies on 1st March 2013.
On the 23rd April 2013, the University of Kwazulu-Natal conferred upon him an honorary Doctor of Science in recognition of his contribution to science and technology in South Africa and the African continent.
He was given the Order of Luthuli in Silver on the 27th April 2013 in recognition of his role in the struggle for freedom.
On the 12th June 2013, the University of South Africa confirmed on him an honorary doctorate in recognition of his contribution to mathematical knowledge and advancement of science and technology in South Africa.