The Greeley-Evans school district has banned children from wearing any clothing with the number 18 on it, not just Denver Broncos gear, since 2011. The rule was put in place a year before Manning joined the team because of its association with a local gang.
A few other numbers are also banned for the same reason as well as gang-related tattoos, shaved eyebrows and bandanas.
The Greeley Tribune reports that district officials say they haven't really had any complaints during the run up to the Super Bowl. Spokeswoman Theresa Myers says people have gotten used to the rule.