Willmott Dixon will now start work in April on the first schools in the £24m bundle of small school projects.
Minister for Lifelong Learning Alun Davies said: “Securing capital investment in these difficult economic times is essential not only for better education outcomes but for the continued support of our construction industry and the growth of our economy.
“This is great news for local people and for the future of education on the area.”
These include Hay-on-Wye Community Primary School (210 places); Clyro Church in Wales Voluntary Controlled School (120 places); Bronllys/Talgarth Community Primary School (150 places); Llangors Church in Wales Voluntary Controlled School (150 places); Archdeacon Griffiths Church in Wales Voluntary Aided School, Llyswen (150 places).