Go ahead and bring your powered boat, canoe, kayak, or even sailboat out to Mono Lake [1]. A parking lot near the water at Navy Beach makes launching lightweight kayaks and canoes reasonable. If you’re putting a heavier boat into the lake, check with the staff at the Mono Lake Scenic Visitor Area [2] for directions to the launch ramp near Lee Vining Creek. Also note that no matter what kind of craft you’re piloting, you cannot beach on the islands April 1–August 1.
During the summer, the Mono Lake Boat Tours (meet at Tioga Lodge, 760/647-6446, www.monolakeboattours.com [3], adults $70, children/seniors $65) offers water tours of the lake. You’ll get an utterly experienced guide who’s been traveling on the lake for ages.
Swimming is allowed (and even encouraged!) in Mono Lake [1] in the summertime. You can swim from your boat, or from any of the unrestricted shore access points. You’ll find yourself floating easily since the salt content of Mono Lake is several times that of the ocean. But take care and watch your kids closely, because no lifeguards patrol the area and you’re swimming at your own risk.
Links:
[1] http://www.moon.com/destinations/california/yosemite-and-the-eastern-sierra/mono-lake
[2] http://www.moon.com/destinations/california/yosemite-and-the-eastern-sierra/mono-lake/sights/mono-lake-scenic-visitor-area
[3] http://www.monolakeboattours.com