The Caltech 6: An All-Woman Chemical Engineering Class

In 2005, six women graduated from the California Institute of Technology and became the first and only all-female chemical engineering class to graduate from an American co-ed university.

Six women who met as one class came from across the county and across oceans, from backgrounds diverse in religion, culture, and economic status, but their experiences are profoundly parallel. Their story reflects how women have evolved as engineers, and the limitations that still exist for them in industry, academia, and beyond.

As the six progressed from childhood to young professionalism, they encountered encouragement and support from parents, teachers, and peers. But they also shared moments of prejudice based on gender, and unequal treatment in classrooms and workplaces. One woman struggled with sexual harassment in her lab. Another watched her female co-workers suggest ideas that got crushed by their male counterparts, only to have those same men suggest the idea fifteen minutes later and get rewarded. One woman is hiding her pregnancy from her boss because when she got married, her company asked if she was still committed to her job long-term. These moments are diminishing in modern society, but they are still prevalent.

According to the latest statistics, women make up only 13% of the engineering workforce. The percentage of females in engineering and computer science occupations has essentially stagnated since the early 2000s, and women across the engineering spectrum earn less than men. For every 100 engineering undergraduates, there are on average only 20 female students. In this world of men, there has only ever been one entirely female class of chemical engineers at a co-ed school, and the Caltech 6 is it.

And yet, when the Caltech 6 freshmen entered a classroom of solely women, they were unfazed. To this day, all six women emphasize how little they thought about the gender of their classmates. Their all-female class was just another class.

For the Caltech 6, their class was just ordinary, but it doesn’t have to be more than that to matter. At times, it is easy to assume that change will come only with extraordinary achievements, or with extraordinary women — women who “prove” females can be scientists. But change is rarely loud or immediate. It is often gradual, established not just by female CEOs or Nobel-prize winning researchers, but by the average female scientist. In this case, by a group of women, working quietly together in a classroom.

Learn more about the Caltech 6 and where they are now.

"The Caltech 6: America's First and Only All-Female Class of ChEs" article originally appeared in the Update section of the January issue of CEP. Members have access online to complete issues, including a vast, searchable archive of back-issues found at


Ayesha Mahmooda's picture

This is a great and interesting story, well done Nidhi!


Wow...these are great people. Can’t imagine how proud their families would be.