I was an avid milk drinker since I was a little kid up until I turned 18. I would honestly drink like 3-5 tall glasses of milk per day. The calcium probably did wonders for my bone health as I've never broken a bone in my life.
However, I then started doing research on milk and apparently the hormones they use on the cows can get passed into the milk and can be pretty bad for you. I don't remember the exact Science around it but I try to avoid milk for the most part now. I'll have it occasionally.
I think it is important for bone health and I would encourage anyone growing to drink it at least a few times a week.