The Magpies are pushing to boost the level of their academy to bring in young talents to the first team.
Brazil is coming in from PSV Eindhoven after spending the last three years with the Dutch club.
Per the club website, Academy Director Steve Harper said: "We're pleased to have been able to add Jack to our coaching staff at the Academy.
"He has great experience helping young footballers work towards fulfilling their potential in good environments and I look forward to seeing his impact on our Under-16s in the future.
"This individual age group appointment, along with the recent addition of Ian Skinner as our U14 Lead Coach, completes our transition from U13-14 and U15-16 dual-age band leads to four lead coaches in the U13-16 age groups, allowing us to provide more detailed coaching support to our young players."
Brazil added: "I'm really happy to be joining such a big club and such a big project in helping to develop, grow and further the effectiveness of the Academy in the coming years. That was a key attraction in taking this role at the club. I want to play a big part of that and seeing where the Academy is going in the coming years was a real attraction to me.
"After eight years of coaching outside of the country, this is my first full-time job back in England and I'm hoping that I can help by bringing some innovative ideas to the Academy from the different environments and cultures I have worked in to potentially add to the work that is already taking place.
"Finally, I feel that the values of the club really align with my own and that was hugely attractive for me. I have a real value on passion and hard work and I'm really excited to get on the grass for the first time next week with the under-16s."