Alumnus vs. Alumna

I recently noticed that badges saying "Teen Ink NYC Summer Writing Program Alumnus" are added to pieces of work written by girls who have attended your summer program. I cringed when I saw the icon for the first time, because it continues to astound me how the editors of a writing magazine consistently make grammatical errors. An alumnus is a male graduate or former student of school, college, program, etc. The Teen Ink NYC Summer Writing Program is for females only; therefore, every graduate of the program would be an alumna. Although this is the only grammatical error I have pointed out, I have noticed other mistakes made by the Teen Ink editing staff. How can you expect to set an example for teenagers when your own grammar is incorrect?