Then one of my favorite bloggers tweeted this on March 5, 2013 about an offshoot using Desmos which led me to Daily Desmos. This site challenges you to match different graphs using Desmos and then send them your solutions. This would be a perfect way to challenge your high level students.
Daily Desmos. Another creative single-serving website from the ever-creative math edublogotwitterwhateversphere. bit.ly/10av4Q7
— Dan Meyer (@ddmeyer) March 5, 2013