This is a formal way to explain that a group of people don't agree on an issue:
There is disagreement among doctors and educators over whether children should be prescribed medication for hyperactivity.
There is disagreement over the practicality of the procedure.
Use "among" to tell what group of people is disagreeing.
Use "over" to explain what the issue is. This can sometimes be "on" instead:
There was some disagreement on where it should be held.