The driver side electric window on my sons Nissan quit on him in the down position. The buttons for the other 3 windows work fine. He can’t bring it in for repair for a week, so I am putting plastic and duct tape on the frame in case of rain.
Is there any temporary thing I can do to get the window up, manually? Some sort of over ride, perhaps?
If you are mechanically inclined, you could remove the door panel and see if there’s a way to manually roll the window up.
I had the same problem a while back, can’t remember the name of the thingie that was broke, but it wasn’t the motor, and it was pretty expensive to replace (around 500 dollars for parts and labor). Here’s hoping it’s not that thingie that’s broken on your son’s car. 
Anyway, my father was able to remove the panel and put the window up, but you might want to tape it in place. My father didn’t, and the damn window worked it’s way down again, bit by bit, every time I shut the door or hit a bump. The dealer was nice enough to put the window up for me again free of charge (couldn’t afford to fix it yet, but I’d brought it in to fix something a bit more urgent), and then they taped it so it would stay up.
You could remove the electric window control and substitute a crank.
Problems are likely: 1) The switch has failed. Diagnose this with a voltmeter to determine if the switch is sending 12 volts to the motor when the ‘Up’ command is selected. 2) The motor has failed. Using a voltmeter, see if the appropriate voltage and polarity is delivered to the motor when the switch is pressed. No year was mentioned in the op, but if the car is old enough, look for a yard that sells parts from wrecks or lets you ‘pull your own’.
This is a good example of why I drive simple cars. I don’t want automatic ANYTHING in my cars. I see gadgetry like that as an nothing more than opportunities for things to break.
My friend once had a similar problem and they charged her around $200 to fix it.
Sure, manually operated stuff break too, but it doesn’t cost you and arm and a leg to fix. And sometimes you can fix it yourself.
I’ve had to repair a few electric windows. In Mrs Geek’s old Nissan Stanza (which we don’t have any more) the mechanical bits that move the window up and down broke. Cheap plastic (grumble mutter complain…). In another friend’s car the switch broke. The worst was my friend’s minivan. There was a sharp bit of metal on the body just inside the door, left over from when it was manufactured. Over time, opening and closing the door caused the wires to slowly cut themselves on this sharp bit of metal, until finally they wouldn’t carry enough current to push the window up, but it would go down.
There’s usually no override, but the door panel is usually held on by a few screws (typically around the mirror and/or door handle) and a bunch of clips. A lot of times the clips are el-cheapo plastic and it’s hard to get the door off without breaking the clips, but generally speaking you can just unscrew the screws and yank carefully and the door panel will come off. If the mechanical bits that push the window up and down are broken, you can usually wedge a stick or something in there to hold the window up and hold the stick in place with a bit of duct tape, which will keep the rain out until you can either get the parts and fix it or (if you are less mechanically inclined) take it to the dealer to fix. If the mechanical bits aren’t broke you can usually force the window into the up position, either by pulling on the part that pushes the window up (which will make the motor spin) or my spinning the motor by hand (slow and painful, but it works).
If your nissan is anything like mine, my money is on the plastic bits.
This happened to my car as well. I could pull the window up with my hands, it just wouldn’t stay that way for long. So I pulled the window (back drivers side) into the up position, and stuck a small suction cup to the window so that the nub part hit the weather stripping on the bottom. It’s been holding the window up ever since (with a little readjustment every couple of weeks). I never really need to put that window down, and I’m broke, so this is as much of a fix as I’ll ever need. It might work for your son until he can get it fixed.
Occasionally the wires going into the door break in the hinge area, from years of flexing. In these cases it’s sometimes possible to get the broken wire ends to touch momentarily with the door open. Hold the switch in the up position while holding the door open – maybe 20% open, maybe 50% open, etc. – you have to experiment. It’s a bit of a long shot, but it’s easy to try and it might work.
If this technique works, the fix is a wiring harness repair in the affected area.