Dejohn has started forming attitudes about different cultural groups. dejohn is about how many years old?

I believe the answer is: 7 years old

On average, children started to develop the ability to categorize things that have similarities on the same group between the age of 7-9 years old.

During this time, children would started to see the characteristics of different cultures and would match it with the cultures that taught to them whcih resulted in different attitudes on those cultures.