Symons, who hails from Hertfordshire, first started playing for Saracens Amateurs and Old Albanians before training with the Saracens Academy.
The six-foot-five giant moved to New Zealand where he came under the wing of former New Zealand international, Aaron Mauger, at Christchurch club High School Old Boys.
The 22-year-old spent time with Leicester Tigers and appeared for the Welford Road club during the JP Morgan Sevens Series in 2012.
Symons has played regularly at fly-half and centre during his career, but is most comfortable in the number 12 jersey, where he is a strong ball-carrier.
Eighteen-year-old Kerry, who was born in Folkstone, was part of the Millwall Football Club Academy before moving to New Zealand in 2007, where he attained a football scholarship with Otago Grammar School.
He played for the New Zealand Under 17s football team before a coach from his school asked him to play rugby.
Kerry progressed into the New Zealand rugby development side and, upon leaving school, featured for West Harbour Under 20s.
The youngster has since moved back to Worcester and signed an Academy contract at Warriors.
Warriors Director of Rugby Dean Ryan said: "I am delighted to welcome Andy Symons and Shay Kerry to Sixways. They are both young players, who are hungry to impress.
"They are the sort of individuals we are trying to develop at Sixways as we build for the future."