Many of the sailors across the remaining seven fleets have guaranteed themselves a medal but the colours are to be decided on the final day with one race on the cards for each fleet.
Tavira's breeze arrived fashionably late but when it came in it remained consistent from the south west building to 10-12 knots.
Spain's Silvia Mas Depares and Marta Davila Mateu wrapped up gold in the 420 Girls fleet after a dominant display on the penultimate day.
A bullet and a sixth leaves them with an unassailable 13 point lead over the chasing pack and they were delighted after racing, “Every sailor always dreams about winning a World Championship and this is awesome for us,” said Mas.
“It's something you train hard for all year and now we're here and now I know we have won. It's something you can't imagine. It's almost like it's not true and I'm very happy.”
A beaming Davila added, “Just being here is amazing but winning it, it's unbelievable. We've won an ISAF Youth Worlds!”
Israel's Yahel Wallach and Stav Brokman have had a strong two days of racing and with a race to go they have sealed silver.
The race is on for bronze with any of the teams placed from third to eighth mathematically able to win gold. As it stands Theres Dhnke and Birte Winkel (GER) hold third spot. Nia Jerword and Lisa Smith (AUS) are currently 9th.
It's a different outlook in the 420 Boys fleet with five points separating the top four. The lead has exchanged hands numerous times throughout the week but heading into final day in pole position is Japan's Ibuki Koizumi and Kotaro Matsuo.
Many of the teams struggled for consistency on the penultimate day but Singapore's Yia Jia Loh and Jonathan Yeo found some form and posted a first and a sixth to advance into silver medal position.
Overnight leaders Diogo Pereira and Manuel Macedo (POR) fell to fourth overall following an 18th and an eighth. Malaysia's Mohammad Faizal Norizan and Ahmad Syukri Abdul Aziz occupy the final podium spot heading into the final day. Emerson Carlberg and Lachlan Gilmour (AUS) are 24th.
There is just one point separating China's Shi Hongmei and Russia's Sefaniya Elfutina in the RS:X Girls with one race remaining. There has been very little separating the top four racers in the RS:X Girls fleet and it will go down to the final day to decide medals.
Italy's Marta Maggetti is six points off the Chinese leader with Pilar Lamadrid (ESP) six points behind the Italian in fourth. Lara O'Brien (AUS) is 13th.
The Spanish racer took the first bullet of the day but it could have been a different story as she explained, “Today was my best day but I could have done it better. I was first in the last race and second in the middle race but finally the girls but passed me but it's okay. I like this wind and I think tomorrow it will be better.
“The first day I was a bit nervous so I didn't have good racing with a seventh and a sixth but then on the other days I improved and I was less nervous and today I was able to win another race. I feel really good because I was at the top with all the good girls.”
Israel's Yael Paz continues to lead the RS:X Boys fleet and sits atop of the pile on 18 points, four ahead of Mattia Camboni (ITA). Australia's Jock Calvert is 26th.
It could have been the perfect day for Camboni with three straight bullets but it was not to be as he explained, “Today was a really good day. I had three firsts but in the first one I was disqualified but I am still second. It was a really good day, the sun was okay and the breeze was quite good.”
Camboni discards his UFD and having previously discarded a sixth he is still within sight of the Israeli. For him to overthrow Paz, Camboni has to finish first or second on the last day and hope the Israeli finishes sixth or lower. Whether it's gold or silver Camboni has thrived in his environment, “This event, it's the best of my life. This is my fourth and last ISAF Youth Worlds so I want to win but if I don't wind it's a nice experience.”
Louis Flament and Charles Dorange (FRA) have an 11 point lead in the SL16 fleet heading into the final day. The French pair discard an OCS and having picked up a ninth on the penultimate day it will all boil down to the final bout.
Jordi and Ruben Booth (ESP) reduced the French duos overnight 15 point lead by four with a steady racing day but will be hard pressed to overthrow them in a single race on the last day. The French and Spanish teams have guaranteed themselves a medal but the colour is to be decided.
Brazil's Kim Vidal and Antonio Lopes hang on to third place overall by three points. America's Ravi Parent and Nicholas Schultz (USA) pulled to within touching distance of the Brazilians and will have one eye on them in the final race. Michelle Bursa and Chelsea Haynes are 7th.
It will go down to the final day in the Laser Radial Boys and Girls fleets with very few points separating the leading racers.
Joel Rodriguez (ESP) leads Singapore's Ryan Lo whilst Seafra Guilfoyle (IRL), who had led from the opening day, falls down to third. The top three have all guaranteed themselves a medal but with seven points of separation the final race will decide the honours. Alistair Young (AUS) is fifth but too far behind to claim a medal.
Race victories went the way of Lo and Jonatan Vadnai (HUN) who is sixth overall.
The top four in the Laser Radial Girls fleet are all in with a shout of claiming an ISAF Youth Worlds medal. Nine points divide Martina Reino (ESP), in first, Haddon Hughes (USA), Maud Jayet (SUI) and Monika Mikkola (FIN). Anna Phillip (AUS) is 10th.
The days bullets were picked up by Julia Kuhn (GER) and Hughes.
Quinn Wilson and Riley Gibbs (USA) moved into pole position in the 29er after the French frontrunners had a disastrous day.
Brice Yrieix and Loic Fischer Guillou had an 18 point advantage going into the day but a discarded disqualification and a 14th sees them slip to second.
From two 29er races the Americans were strong and focused and posted a third and a bullet. They lead on 41 points followed by the French on 42 points.
Markus Somerville and Isaac Mchardie (NZL) are within touching distance of the top two on 48 points. James Colleyand Shaun Connor (AUS) are 11th.
One single race in both fleets is scheduled to commence at 13:00 local time.
View results here.