No, a 17-year-old cannot go to Mexico without a passport if they are traveling by air. Under current international regulations, all travelers, regardless of age, must present a valid Passport Book to enter Mexico via an airplane. If the 17-year-old is a U.S. citizen traveling by land or sea (such as driving across the border or on a closed-loop cruise), they have a bit more flexibility; those under 19 can sometimes use an original birth certificate or a Consular Report of Birth Abroad. However, Mexico’s own immigration authorities have tightened their rules, and they almost universally demand a passport for entry into the country. Additionally, because the traveler is a minor, they should carry a notarized letter of consent signed by both parents allowing them to travel abroad. Without this, they risk being detained at the border or denied boarding by the airline, as authorities are highly vigilant about potential international parental abductions or runaway situations involving older teenagers.