We've tried the quiet time too but that normally leads to all those jumping on the bed episodes that DD loves so much...

What has been working for us for the last couple of days at least (no clue how long our good luck will hold!) is that we've been having an enforced wake up time (at 7:30 am) and we take DD for a walk right before bed time. We're hoping to stretch this out for as much as it's worth!