The Western Algarve is also quite breezy, the further west the breezier really.
Maybe Lagos as that is pretty lively during late July/Aug for your teen. Not clubby in the way of an Ibiza or Ayia Napa, but loads of bars and restaurants and lots of atmosphere. Just dont try and park anywhere , make sure you can walk in to the town -it's kind of pedestrianised, also has a Marina area with a few lively bars.
Not much for teens outside of the six weeks of the school holidays, the far west has a surfer scene but I think you would need to be an experienced surfer or take lessons to surf there, as it looked pretty wild to me looking down at it from a cliff edge.
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mega popular though.
Mmm think I might be talking myself into going back there next summer.