i like Aimee V's response. (btw ADD is total BS! please don't buy into that!)
Your child is a Pisces Tiger with a moon in Taurus. All of these signs point to having intense and passionate emotions. She's daydreaming while she's working - that's the Pisces in her. Tigers also can go through more intense mood swings, but they also are magnetic & self-possessed.
I'm not going to detail these signs here. You can link to: http://www.astrology-online.com/pisces.htm, and http://chinese.astrology.com/tiger.html, and http://www.cafeastrology.com/print/moon_in_taurus.html for more info.
I think when we understand how someone "ticks" it's easier to figure out creative responses that work for them.
I think Aimee V's suggestions work since her child is nearly the same astrologically, and by offering these rewards - esp. the emotional ones, it's a good incentive.
I don't think your child cares too much about reaping material benefits, but really enjoys the social and esp. artistic benefits. Perhaps giving her constructive artistic possibilities that she can do BEFORE you get home, and show you when you get home, would get the "daydreaming" stuff out of the way, and let her focus on homework afterwards.
Obviously, up to you how to arrange this. Hope this helps. Peace!