Year 2 wanted to find out the best way to remove bacteria from their hands. They set up an investigation using oil and flour and explored whether rubbing their hands together, washing in cold water, warm water or warm water with soap was the best way to get them clean.Year 2 wanted to find out the best way to remove bacteria from their hands. They set up an investigation using oil and flour and explored whether rubbing their hands together, washing in cold water, warm water or warm water with soap was the best way to get them clean.