Editor's note: Cao Zizi is a teacher of first-year junior high school students in Shanghai.

I was born in the 1970s. Very few of my peers dared to write notes or letters to express affection or love when we were in junior high school, although we developed crushes on boys, of course.

I would put my bicycle next to that of the boy I liked, to increase the chances of an encounter. I would watch him playing basketball from a distance, feeling the happiness and sweetness in my heart. I even celebrated when I found that I had achieved the same test score as him. I never told him how I felt, because I wanted to keep everything pure and beautiful.

Once, one of my friends secretly gave me a piece of paper and asked me to pass it on to a boy. That was usually how a "love letter" was delivered in our day if there was such a thing.

However, today children express their affection directly and publicly through text messages and letters, usually in amazing numbers and without the use of an intermediary.

But the way they express their affection is not really very forceful. They give gifts on Valentine's Day, mostly in the form of dolls, and they routinely exchange small toys and gadgets. However, some of the girls may be a little too materialistic.

Parent's attitudes have also become more tolerant: They remind their children to prioritize academic study, because they know that any interference will be ineffective. Children of this age will usually do the exact opposite of what's asked of them.

I think this is progress with the times. It is too extreme for some parents, who forbid love in high school, but then require their children to be in a settled relationship when they first enter college. How can that be possible?

I am not in favor of children kissing and hugging in the street, but I think most have good self-control and cases of unmarried mothers are still rare in schools with good ethics.

Cao Zizi talking to Zhou Wenting.