I tinker with computers as a side hobby and I just started getting hip to the Apple stuff about a year and a half ago. Here's what I've learned so far - I hope it helps:
Apple is pretty big on planned/perceived obsolescence. They would have you think that you need to upgrade your entire rig to keep up with the latest software, but the dirty little secret is that their hardware is so darn fabulous, you don't need to.
Case in point: early last year I found an old, first-generation Mac Pro (the big aluminum one), a 2006 model, at a thrift store . The thing worked flawlessly so I snagged it and took it home to tinker with. Apparently the previous owner gave it away because it would not run the latest operating system or any current software - mainly because Apple engineered the model that way. Long story short, within a month I found out how to re-code the machine so that it actually would accept the necessary upgrades, and I am proud to report that the beast is currently running Yosemite 10.10, handling all my music programs without a hitch, and with a couple more upgrades (processors, hard drive) that bad boy will be handling it's business for the next few years to come.
As far as MacBook Pro's are concerned, I've found that if you're not a graphic designer and in need of the Retina display, a maxed-out 2011 or 2012 model is sufficient for anything you'd need to do (heck, I'm typing this on a 2011 model right now). Again, the hardware is still superb and the price point versus an entry-level MacBook Air makes it worthwhile.
A refurbished 2012 MacBook Pro with an i7 processor, 16GB of memory and a solid-state hard drive (or 'SSD') will handle anything your daughter can throw at it - and probably drive her to school as well!...