Britain's Jessica-Jane Applegate set a Paralympic record to win gold in the women's S14 200m freestyle final.
The 16-year-old, who has Asperger's syndrome, clocked two minutes 12.63 seconds to beat Australia's Taylor Corry by 0.55 secs.
Applegate, who qualified fastest after breaking her own British record in the morning session, was third with 50m to go before a storming final length.
Hannah Russell and James Clegg both won bronze in the S12 100m butterfly.
Applegate joins Ellie Simmonds and Jonathan Fox as Britain's gold medallists at the Aquatics Centre.
"I am ecstatic. I didn't think I could do something like that," she said.
"It means so much. I just want to thank my mum and my family and everyone who's supported me. I'm on cloud nine at the moment."
Applegate, who was fourth in the 100m backstroke, added: "At the last turn I could see how far ahead they were and I knew I had to give everything I had. It was my last race so I knew it didn't matter if I collapsed at the bottom of the pool, it's fine."
Russell added bronze to the silver she won in the 400m freestyle, while the 18-year-old Clegg touched out in a close finish to claim third in 1:00.00 after turning at the halfway point in fifth.
Applegate's team-mate Natalie Massey came home sixth, while in the men's equivalent, Daniel Pepper and Ben Procter finished seventh and eighth respectively.
In the women's S13 100 freestyle, Britain's Rhiannon Henry was fourth, while Britain's Heather Frederiksen finished sixth in the final of women's 50m freestyle final S8.
There was more disappointment for Britain as Sean Fraser, Thomas Young, Sam Hynd and Robert Welbourn failed to defend GB's 4x100m 34 points freestyle relay title, finishing fifth as Australia clinched gold.