The relationship between water, oxygen and the brain is not a phenomenon. Water adds oxygen to the brain which is used faster during testing. Students should be well hydrated as though they are preparing for a physical competition (running, jumping, swimming, bicycling, etc.) It is advisable that your child drinks water before testing and during test breaks because it allows the brain activity to increase. It is a proven fact, oxygenation of the brain is vital and water is the secondary substance to air intake (breathing).