Lindsay Lohan -- The Clock Is Ticking

5/13/2010 9:00 AM PDT BY TMZ STAFF
Lindsay Lohan has exactly one week to make up 4 alcohol ed classes ... or else she's going to jail.  Problem is -- Lindsay is still 2,475 air miles from the school of higher alcohol learning.

Check out Lindsay in NYC yesterday.  She says she is in the city to be with her mom, whose brother died a few days ago.

Lindsay is due in court next Thursday in her DUI probation case.  The judge has made it clear -- if Lindsay violated her probation she's going to jail.