He is now ranked 14th in the world in the under-18 age group and his winning throw qualified him for the world youth championships in Ukraine next year with almost 6m to spare.
Fafeita threw 50.91m in the discus, placing second behind Richard Calister (Westlake Boys) who recorded 53.76m. Tim Girling-McLean (Rathkeale College) was 15th with a throw of 40.12m.
Bloxam picked up his second title in the shot put with 18.32m. Fafeita was second with 17.44m and Girling-McLean seventh with 15.69m.
In the junior girls hammer throw Emma Kruszona (Wairarapa College) placed fifth with 39.30m and Grace Quinn (Solway) ninth with 26.79m while Katie Smith (Wairarapa College) was ninth in the senior girls' discus with a throw of 27.56m.
On the track Alison Andrews-Paul (Wairarapa College) and Molly Creagh (Wairarapa College) qualified for the final of the junior girls and senior girls 800m respectively as did Edward Hewitt (Rathkeale College) in the senior boys 400m.