One thing that I think would have a massive positive impact on society, and something that is within the legal purview of the President to change with Executive Order, would be to reschedule cannabis from schedule I to something more reasonable. I'm not sure if that alone is enough to technically decriminalize it at the federal level, but it's an absolute travesty that it hasn't been done already. I'm honestly surprised more people aren't upset at Obama for not doing that before leaving office.
You're President for a day. The Don is off getting his new toupee or something.
You're allowed ONE unilateral motion -- one executive order.
What do you do?