I've been convinced to give up one day in Colorado Springs and add a day in Vail or Breckenridge. That means I get 1 day in Boulder and 1 day in Vail/Brechenridge. What are the must sees in those two areas?
(Family of 4 - 2 girls 17/20)

What time of year are you going?
There are lots of fun things to do in Vail.

Next Week landing in Denver - Staying at Brown Palace Aug 6&7. Committed to hotels in Colorado Springs 8, 9, 10 and staying in Boulder Aug.11. Would like to skip one night in colorado springs (if I can - did priceline!)and try to do at least 1 day in Vail and Boulder. Too much? What are the must see with 2 teenage girlds?

Not sure I understand your itinerary, but you won't be able to do both Vail & Breck in one day. It's not actually impossible but I certainly would not recommend it.Likewise neither will you be able to do Boulder and Breck or Boulder & Vail in one day.I think you meant one day in Boulder and one day in either Vail or breck. Right?

The girls might like to shop the Outlets in Silverthorne (Dillon/Breckenridge).

Yes, we will be spending one day in Boulder and one day in Vail - any suggestions?

We had a wonderful meal at Sweet Basil in Vail Village. I can highly recommend.

In Boulder: Drive up to Chautauqua park at 9th and Baseline and have lunch at the old Chautauqua dining hall. Continue west on Baseline and drive up Flagstaff mountain as far as the first parking turnoff to get a great view overlooking Boulder. Head down to the Pearl Street Mall and spend a couple hours wandering the streets. Walk south until you hit Boulder Creek and take a walk along the creek bicycle path.