Hi,
From my experience, the weekdays and weekend basals work very well but only during term time. However, it all just goes haywire when the long school holiday break starts...and that's when you need to think about another basal profile i.e. inactive holiday basal, which might be slightly more than the weekend basal. As mentioned earlier, this will also have a spill over effect on bfast, lunch and dinner ratios!
Also, I noticed from your reply that your daughter wakes up at 11 am. What I have experienced with my son is that when he wakes up late he needs a very high temporary basal for 2 hrs atleast....may be some kind of a liver dump happens!!. The best way to find out is to test as soon as she wakes up, and then test again right before bfast ...For example yesterday my son woke up with a perfect 5.2 at 11.30 am and was 7.8 right before bfast around 12.15 p.m....within 45 minutes!!! I know that it is not a basal issue as the same basal profile worked fantastically well the day before and even today....not sure why this happens only on a few days...may be to do with how active/inactive he has been the previous day, etc. But I have noticed this on a few odd days during long holidays, and didn't come as a surprise. Only because I make him test right before bfast as well as when he wakes up (only during holidays...as i know this is a lot of testing especially in a short span of 30-45 minutes), it was easy to detect and correct so his levels were ok before lunch. Depending on the difference between his waking up levels and levels before bfast, we also then adjust the bolus ratios accordingly as well as the basal.
Yes, I think you are right in thinking that if the basal is too low then the correction doesn't work...atleast I have noticed the same as well!
You might want to try the method suggested above before bfast, and then try temporary basal rates(a % increase over and above the weekend basal) for the rest of the day...and depending upon what works you may then set that as the holiday basal.
Unfortunately, it is all a bit of trial and error, which may be due to teenage issues to do with puberty, hormones, etc. Hope this helps!