Hayley, 16, who goes to Yarborough School in Lincoln, will compete in the 50m and 100m freestyle and relays against the nation's school-aged elite at the Sunderland Aquatic Centre, in September.
The athlete, a member of Lincoln Vulcans, said it was an honour to represent her country.
GB athlete and Olympic gold medallist Rebecca Adlington said the contest was a fantastic opportunity for young athletes like Hayley to get a taste of elite competition.
She said: "Congratulations to Hayley on being selected to represent England in the Sainsbury's UK School Games.
"It is a fantastic achievement and something which she should feel extremely proud of.
"I hope Hayley benefits from the competition and it proves invaluable in preparing her for her future and I wish her all the best."