First steps alone

We live more than a mile from school, so it's not practical for Zach to walk all the way there and back everyday...  However, we wanted to give him a chance to practice walking alone and figured that the streets right around school provided the most controlled, safest environment to begin.  (Let me be clear here - I park a block away and watch him walk this straight shot back to the car, but he thinks he's a big shot!)

Where did the time go?  When did we ditch the stroller for this?