16. Raiders
Number of mascots/nicknames: 377
More than 300 high school in the US have raiders as their mascots. The most popular one is not a high school mascot, but the mascot of the professional American football team, Oakland Raiders.
15. Cardinals
Number of mascots/nicknames: 407
Cardinal birds as mascots can be in red or in blue. When they are red, like the mascot of the Arizona Cardinals, professional American Football franchise, they seem pretty fierce. Red is a strong color that inspires passion, which is good for sports spirit. As for the blue cardinals, I presume they have its perks, which is why around 400 high schools have picked this little bird to be their lucky charm.