Everyone should try to drink at least eight glasses of water a day to maintain a healthy lifestyle.
Kidney disease
The body is full of lots of different chemicals and water helps to keep them in check.
Not drinking enough water when you're young can sometimes lead to long-term problems of infection, kidney disease and high blood pressure.
The decision to put water coolers in schools in Yorkshire comes after Yorkshire Water put them in three schools in Leeds.
The experiment went well and has prompted Yorkshire Water to extend the scheme.
Now, each time a local company leases three water coolers, a fourth one is given to a local school free of charge.