Every year at the Swim Coaches meeting prior to the start of the season we toss a coin to determine whether the 11-12, 13-14 and Open relays will be freestyle or medley. Yes, we literally toss a coin.
8 and under girls and boys and 9-10 girls and boys are always freestyle.
Here are the results for 2016 for 11 and up:
11-12 girls: Medley
11-12 boys: Medley
13-14 girls: Freestyle
13-14 boys: Freestyle
Open women: Freestyle
Open men: Freestyle