Napier Boys' High School's Thompson twins, Tyrone and Leo, played for the New Zealand Maori team.
Udy-Johns pointed out halfback/first five-eighth Brian Lealaifano of Auckland's Sacred Heart College, who won the 12-team boys tournament's MVP award was outstanding for the hosts.
Udy-Johns will begin a two-year academy contract with the Hawke's Bay Rugby Union next year but has yet to decide whether sevens will become more a priority for him than 15s.
"I'll just take whatever comes," he said.
Seventeen-year-old Ah Kiong will return to Hastings Boy's High School for Year 13 studies next year.
"This was a pretty unreal experience. I still can't believe we are world champions ... it's taking a while to sink in," Ah Kiong said.
He was mostly used as an impact player in both the halfback and first five-eighth positions. He said having his parents, former Hawke's Bay Sevens player Herman Ah Kiong and former Hawke's Bay basketball and netball rep Cheleme Smiler and Udy Johns parents Phil and Tania among the spectators made it particularly special.
"This title is for our families and our country," Ah Kiong said.
The grandson of former Hawke's Bay Magpies rugby team midfield back Wini Smiler said the weekend's success has made him determined to go as far as he can in sevens.
"I still don't mind which position either. While I learnt a lot off Brian [Lealaifano] who is a nice player Niko's composure and leadership qualities were unbelievable," Ah Kiong said referring to their New Zealand team's captain Niko Jones, a son of All Black legend Sir Michael Jones.
"Niko has been there and done that. His voice was great."
Jones captained Auckland's St Peter's College first XV to a 31-28 victory against Napier Boys' High School in the final of the National Top Four tournament in Palmerston North in September and last month secured an All Blacks Sevens contract.
Expect plenty more to be heard of Udy-Johns and Ah Kiong in the future. Helping teams finish first and second at world championship level in the same year is a massive achievement.
Meanwhile the Maurice Trapp Group Hawke's Bay men's sevens team finished sixth at the 16-team TECT Nationals which ended in Tauranga today. The Ellery Wilson-coached side lost 19-5 to Taranaki in the Plate final.
In their Plate semifinal Hawke's Bay beat Southland 21-7. They won their pool after losing 17-12 to Canterbury and beating Taranaki 38-12 and Bay of Plenty 21-17.
Wilson was happy with the improvement on last summer's 11th placing. He was also pleased with the ticker his troops displayed after losing forward Damien Scott to injury in game two on Saturday and speedster Mitch Drew to injury in their Plate semifinal.
"The boys have had a taste of the top eight now. They are all available for next year when we will be back to make another leap," Wilson said.
He was impressed with the form of Sebastian Visinia and Saia Paese in the games won. Captain and prop Teihana Brown played every minute of every match while inside backs Trent Hape and Zac Donaldson played most of the minutes.
The Hawke's Bay women recovered from a 14-0 deficit at halftime to beat Taranaki 17-14 in the playoff for 11th in their 12-team nationals.
They had earlier lost 26-17 to Tasman in the Bowl semifinal after losing 22-12 to Bay of Plenty, 50-0 to Waikato and 14-7 to Tasman in pool play.
"We really stepped up in the second half of our last game. We brought a young team with the aim of developing for the future ... only three of us are over 22," Black Ferns pivot Krysten Cottrell said referring to herself, captain Shaylee Tipiwai and Julie Ferguson-Ngawaka.
"Apart from the Waikato game we stuck together pretty well," Cottrell said before singling out secondary schools players, prop Liana Mikaele-Tu'u and halfback/first five-eighth Cortez Te Pou as players to keep an eye on in the future.