In Spanish, there are many nouns which end in a “o” if referring to a male, and “a” if referring to a female. For example: chico/chica (child), maestro/maestra (teacher), hijo/hija (son/daughter). The nouns are pluralized with an “s”. So a group of boys is “chicos”; and a group of girls is “chicas”. In a mixed group, the male version is always used. So when we are talking about 99 girls and 1 boy, it’s “chicos”. To some people, the masculinization of mixed plurals seems unfair.
While in Spain last month, I found that some Spaniards have invented a new plural form. When writing about a mixed group of boys and girls, they write chic@s. Pretty clever, in my estimation. Except for the problem of auto-correct trying to convert the word into an e-mail address. The new letter “@” is not yet part of formal usage. I read a variety of newspapers, and never saw the @ used as a letter. But on the Madrid subway, some cars have slim TV monitors attached to the center poles, and those televisions show short news items and commercials, along with captioning. On one news report, I did see the “@” used in the captioning for a mixed-gender plural.
In other Spanish alphabet news: The Spanish Royal Academy has voted to remove “ch” and “ll” from the official Spanish alphabet. Further, the names of two other letters have been changed. “V” is now prounounced (in Spanish) “uve” rather than “ve”. Further, “Y”, which is traditionally called “i-griega” (“Greek i”) may now also be called “ye”.
UPDATE: Although the use of “@” as a letter is new to me, some commenters point out that it’s been around at least since the 1990s.