Friday Evenings: Slack Key Guitar Concerts. Traditional Hawaiian slack key guitar and `ukulele concerts. August 7 – For the Birds; August 14 – Sea Turtle Serenade; August 21 – Ohana Slack Key Guitar & Ukulele Concert; August 28 – Heart of Slack Key Guitar & Ukulele Concert. Free gift drawing. Tickets: $20 ($15 keiki/seniors). Slack key guitar and `ukulele in the real old style.  All traditional music with songs and stories of the islands, telling the history of this Hawaiian musical…