The Grand Central Academy in New York will be hosting a Portrait Sketch Competition later this summer. Ten contestants will each paint six one-session portraits over the course of three days, from August 27-29.
The portraits will be judged as a group. First place is $1500 and second place is $500. There's no application fee, and it's easy to enter, but just be sure you do so by July 1. Here's the link to the online application form.
The painting above is by Sargent, who won't be in the running.