Danielle Christmas won the intermediate under-17s race for England in the Home Schools international.
The Crawley club runner, representing Surrey, clocked 4min.24.2sec at Chelmsford.
Andrew Donno, 17, of Brighton and Hove, was second in the 2,000m steeplechase when he competed for Wales under-20s against Welsh Schools and Colleges at Brecon. He won a bronze medal in the Welsh Championships last month.
Brighton and Hove are closing on promotion to the southern premier division of the National Young Athletes League.
They need to beat Aylesbury in division one east on August 1 and hope Ealing and Southall finish ahead of Poole and Wycombe.
Brighton won their final home match of the season at Withdean from the Isle of Wight, Guildford and Godalming and Team Solent.
Jenny Coe, after winning an under-15s bronze at the All England Schools, was first in the long jump (5.01m) while Charlie Harper took the 80m hurdles (12.2sec).
Elliott Green and Gus Kennedy deadheated with 27.8sec in the under-13s' 200m.
Amber O'Brien claimed the high jump in the same age group (1.36m).
Daniel Stepney triumphed for Brighton and Hove in the intermdiate 1,500m.
Brighton manager Lesley Parsons said: "We've had a good season and promotion would be a great way to finish it off."
In other fourth round matches in division one east, Hastings were first, Lewes third and Horsham fourth. Chichester were second and Worthing third in divison one west and Crawley finished fourth in the southern premier.
Meanwhile, Eastbourne have won the East Sussex Under-13s League title from Lewes, Phoenix (Brighton), Hastings and Brighton and Hove. Horsham claimed the west crown from Worthing, East Grinstead, Chichester and Crawley.
Katy Moore, 17, from Brighton, was second in the 17-to-20-year-old age group at the national duathlon at Llanelli.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article