A juvenile group of the World Health Organization published a report, based on an investigation into the growth and development of children in various countries. According to the report, the growth rate of children is different in the four seasons. The fastest growth is in May, with an average of 7.3 mm, while the slowest growth is in October, with an average of only 3.3 mm. Therefore, relevant experts at home and abroad have called May the "magic month of May". How can parents take advantage of this critical opportunity?