The Kansas City Chiefs had the day off from practice on Wednesday, but that didn't stop linebacker Derrick Johnson from going to work.

Johnson hosted 545 kids from schools across the Greater Kansas City area at Arrowhead Stadium on Wednesday night as part of his fourth annual "Gearing Up!" back to school event. The kids toured the stadium before meeting with Johnson in the Chiefs Sports Lab and receiving a backpack full of school supplies.

"What we've noticed is that if you ask most of our elementary school students what they want to be when they grow up, they typically say that they want to be a professional athlete," said. Dr. Anthony Lewis, the Assistant Superintendent for Kansas City Public Schools. "It's important for them to see a professional athlete like Derrick coming out here and caring about their education."

The son of a school teacher, education has been a priority throughout Johnson's life.

"My passion is working with kids, especially underprivileged kids from low-income households, and letting them know how important education is," Johnson said. "That's how I grew up – my mom has been a school teacher for over 40 years. She instilled in me some great values and I want to give that back to the kids by doing little things like this."

The event has grown significantly since its inception in 2014, when 150 kids kicked off the school year with Johnson. That number grew to 300 kids the following year before eclipsing over 500 kids the past two years.

"They just see the end product of him on the field, but they don't know the steps that he took to get there," Lewis said. "He once was in third grade and in sixth grade. For him to care about their education and for the kids to see that, it's huge."

There was also face paint, a balloon artist, caricature drawings and food available for everyone in attendance.

Johnson's philanthropy, the Defend the Dream Foundation, aims to "provide low-income and inner city young people with opportunities and resources to reach their full potential," according to the foundation's website.

In addition to the Gearing Up! event, Johnson has also opened several "Discovery Dens," or rooms designed for reading and education, in schools across the Kansas City area.

"My influence can have a big effect on younger generations, so what better way to try and make an impact than to tell somebody what you believe in?," Johnson said. "I strongly believe in education so that they can better themselves in their lives and be successful. When they shake my hand and I give them a backpack or a book to read, they think it's pretty cool and I do too."

Johnson returns to the field on Friday night as the Chiefs open the preseason against the San Francisco 49ers. Catch the game on KCTV5 at 8 p.m.