My tablet will not turn on,

Which tablet do you have? Most modern tablets usually use a standard micro USB wire. You will need to find out which adapter you need to plug into the wall.
You can also charge it with the cable from a computer or laptop. This method is slow and it can quickly flatten the battery on the laptop if it's not plugged into the wall supply.

Make sure the power cord is plugged into the computer and the wall and if it still wont turn on try wiggling the power cord connecter where it goes into the tablet .or hold the power button down and see if any lights flash on at all

Sounds like the battery has failed. The battery must be good for the wall charger to run the computer, it will not run solely on the charger.

The charger plug should plug into the mini-USB port. This is the same port for the USB cable that would connect to the computer, and in fact the tablet can be charged from the computer if the computer is on.

The wall charger is faulty! Do you see any indication on the Nabi that it is charging when the wall charger is plugged in?

Depend what model "this tablet" is. Generally tablet chargers have a USB connector at the wall plug end , plugged into the wall charger and a mini usb or proprietary connector at the tablet end. The USB connector can also be plugged into a USB port on a computer or other device. Charging rate will depend on how much current the device can deliver to the USB port, they are not all the same.

Plug it in to a wall charger for ten minutes and try to turn it on. Maybe the ipad doesn't charge with comouter. Or reboot it by pressing home button with top right button on ioad and hold until responds. That can take a minute.

Plug it into the wall or a computer, if it does not turn on after a minute or so do a hard reset- hold down the power button and the center button down at the same time until the apple logo appears on the screen.

When a tablet is completely dead you will need to charge it from a wall plug and not a computer. Also try holding the power button for 20 seconds, it is possibly frozen.