“Girls like you shouldn’t be in this program.”

Just a few seconds before, AP Computer Science teacher Judi Heher, then a sophomore at University of Waterloo in Canada, had simply raised her hand to ask a question about a math problem.

Her professor in Pure Algebra turned from the young man he had just finished helping and stared blankly at Heher. With a look of disgust, he rubbed the piece of orange chalk in his hands and hurled it at Heher before proceeding to tell her that because of her gender, she did not belong in such an advanced mathematics program.

Flustered and unable to respond, Heher stormed to her dorm room, determined to pack her bags and return to California. With every jacket she folded she felt even more “stupid” and doubtful she could survive in such a rigorous program with a 15-to-1 male-female ratio.

Just as she was ready to leave, her boyfriend turned her helplessness into determination, convincing her to let out her frustration by proving her professor wrong. After spending the entire weekend studying for her math midterm, Heher received the second highest grade in the class.

Though this event took place over 30 years ago, the memory has served as motivation in other aspects of her life.

“I remind myself of [that experience] a lot when I get into places where I don’t think I can do things, because I can,” Heher said. “I just need to remind myself that I’m capable of doing it.”

According to the Washington Post, 80 percent of women across the nation in STEM fields say they have been discriminated against, contributing to a gender gap in these fields. This gender divide, according to the National Girls Collaborative Project, means that although 47 percent of the total U.S. workforce are women, only 13 percent of engineers are women and 25 percent of women are in computer and mathematical sciences.

Teachers and students say that there has been a growing movement to end this disparity, but the efforts are only now beginning to achieve results.

Why are there fewer women in STEM?

Before the gender gap in STEM can be eliminated, those in these fields say its root causes must be understood. However, there are differing opinions on the primary cause of  the gender disparity.

AP Biology teacher Cheryl Lenz noted the effects of media coverage of gender discrimination, life choices and the perception of a “boys’ club” in different STEM fields on women’s career choices.

“You read about companies that treat women poorly, so women don’t want to go into those fields,” Lenz said. “Women also have to think about what’s really important to them in the big picture, and so in some fields it’s easier to balance your life and raise a family versus other fields.”

Heher said women’s traditional devotion to family is a major factor of the gap and a reason there are fewer females in STEM leadership positions.

“Some of [the limited opportunities to move up] happen because of the choices we make as women in terms of how much time [we] want to put in and how much grief we’re willing to take, how much travel we’re willing to do,” Heher said.

Heher reasons the gender gap may have formed because having families for the majority of women often results in reduced mobility in their jobs.

Some highly paid women, like Marissa Mayer, the CEO of Yahoo, and Sheryl Sandberg, the chief operating officer of Facebook, have chosen to hire nannies and return to work within three weeks of giving birth.

According to Facebook’s global diversity report in June 2014, its employees are 69 percent male and 31 percent female, while “non-tech” jobs at Facebook are 53 percent male and 47 percent female.

Math and computer science teacher Debra Troxell pointed to a different source for the gap, suggesting that the disparity between the genders is clear from a young age.

“It’s just the things you hear all the time. ‘Girls, don’t do that.’ When you’re 5-years-old, boys play with cars, girls play with dolls,” Troxell said. “It’s just a stereotype that’s going to take generations to get over, and the faster we get over it, the better.”

Comparing the gender divide in different education levels

To bridge this gap, both high schools and colleges are working to include STEM programs that encourage students, especially girls, to join these fields.

For instance, Saratoga High programs like robotics are meant to help guide both male and female students move into math and science-related fields. According to junior Rachel Won, however, a gender gap exists even in these organizations.

Won said that in her freshman year, there were about three girls and 17 boys in robotics, but recently there has been a small increase to eight girls and 25 boys. Won pointed out that although there is some improvement, the genders in the group are far from balanced.

Although Won was only one of three girls when she first joined the program, she said that it did not affect the quality of her experience.

“The [boys in the robotics team were] super friendly and weren’t intimidating towards girls,” Won said. “It was a really good environment to start learning, so you don’t really realize you’re [one of] the only girls.”

The gender disparity in the robotics team seems to be mirrored in advanced STEM classes.

In AP Calculus BC, there are 28 females and 46 males, as opposed to the less rigorous AP Calculus AB, which has 73 females and 57 males.

Math and engineering teacher Audrey Warmuth attributed the higher number of males in AP Calculus BC to self-confidence rather than to ability.

“Boys are a little more confident, so if they don’t understand something, they blame it on circumstances as opposed to say, ‘It’s me, I’m not smart enough,’” Warmuth said. “Girls tend to internalize things more.”

One of the few exceptions to male dominance in AP STEM classes at the school is in AP Biology, where 53 percent of the class is female. By contrast, AP Physics is only 31 percent female.

The nonprofit professional feminist organization Sociologists for Women in Society has found that gender discrimination causes women to choose biology over sciences with more difficult, abstract math, such as physics. In addition, its surveys have found that biology is more closely related to “emotional labor” and is regarded as more feminine and acceptable to women.

The difference in confidence between males and females varies not only in class choices, but also between what they study in college. In UC Berkeley’s electrical engineering program, nationally ranked in the top three engineering programs, only 12 percent of students are female, according to the university’s student newspaper, The Daily Californian.

Class of 2012 alumnus Manish Raghavan, who is studying electrical engineering at UC Berkeley, has seen that the gender disparity significantly worsens in college. He noticed that highly ranked college STEM programs have are extremely male-dominated.

“I never noticed a gender gap at Saratoga,” Raghavan said. “Most classes I took were pretty balanced. At Berkeley, I've found that the gender gap is most pronounced in physics and computer science classes.”

Raghavan attributed the increased gender divide in higher education to the fact that in high school, students are required to take math and science classes, whereas in college, students self-select these courses. He suggested that fewer females select male-dominated STEM courses because they have fewer women to look up to who have already taken those classes.

“It makes them hesitant to enter [those STEM courses]. It’s tough to put yourself in a situation where you’re a minority,” Raghavan said.

Is the gap closing?

Troxell said that as the gender gap in STEM has gained national attention in recent years, numbers for women in STEM have improved.

“There are national promotions to get young kids, old kids [and] girls programming,” Troxell said. “I have seen a consistent positive trend in equaling out the gender in my classes, which is amazing.”

Troxell remembered being the only girl in her engineering class of 35 in college and seeing only two or three girls in the computer science classes she taught years ago. This year, in the AP Computer Science A classes, there are 39 females and 52 males, demonstrating that awareness of the disparity has translated into more equal gender ratios in some STEM classes.

The national movement can be seen in companies like GoldieBlox, which is now making toys that specifically target girls in order to stimulate early interest in STEM and “inspire the future generation of female engineers.”

According to GoldieBlox’s website, 86 percent of engineers are male, and with its “Parade Float” construction kit and “girl inventor” action figures, it aims to change that percentage.

On the other hand, Won said that the gender gap is only perceived to be closing quicker by people living in the Bay Area than in many other places.

“No matter if they’re a girl or a boy, white or Asian, here, everybody’s entire childhood is immersed in STEM,” Won said. “It’s just the environment that we live in.” She said such an environment wouldn’t be as common in less tech-centric places like Ohio and Kentucky.

According to students and faculty, the STEM gender gap seems to be narrowing quickly in Silicon Valley. However, statistics regarding college students and the overall STEM workforce demonstrate a much slower closing of the divide. It appears that while the awareness from students and teachers of the gender gap is rapidly growing, the resulting improvement is gradual.

Students, like Won, who have joined STEM programs believe that females should not be afraid to enter the field despite the male dominance.

“First of all, you can get a smart date,” Won joked. “You should [also] be proud you’re a woman trying to compete with guys [in such a male-dominated field].”

Though Won said it is unfair for women to have to put themselves more out there than men in STEM, Won added that it is crucial for everyone to find a way to show his or her presence in any field.

“You have to find a way to get respect,” Won said. “That’s going to happen no matter where you are, whether you’re a woman or a man.”