HOUSTON – From NASA to the Astrodome, Houston is packed with history. Sure, you can crack open a book, but there's a way you can take it all in on the Houston History Bus for free.

From aboard an old converted school bus, Mister McKinney shares his passion for Houston's history.

"We're going to teach you about your local neighborhood or communities that matter ... like the Heights that has been around for over 100 years," McKinney said.

The Houston History Bus focuses its tours on specific areas of Houston. Its most recent route will begin rolling through the Houston Heights, passing historic Queen Anne Victorian homes and famous landmarks like the historic Heights Fire Station.

Guests will also see Harvard Elementary, one of the oldest schools in Houston. It opened its doors in 1898, even before Houston ISD existed. McKinney helped the school celebrate its 120th birthday this week with a celebration and a history lesson.

"Y'all had a trolley line. Can anyone guess where the trolley line ran?" McKinney said as he quizzed the fourth-graders aboard his bus.

"The Heights is the oldest neighborhood in Houston," said Harvard Elementary School Principal Laura Alaniz. "So, I think it's so important for students to learn about their history because it gives us a sense of pride, ownership and it just builds community."

"That's the whole idea, is free education," McKinney said. "Get people excited about their neighborhood and build future preservationists ... young people to get inspired about what is going on in their neighborhood."

Each tour lasts 50 minutes.

The Historic Houston Heights tour starts at 5:30 p.m. Friday and runs all weekend and the following weekend as well. There are only 20 seats on the bus, so you have to reserve your spot here. Your ticket is free when you like Mister McKinney's Historic Houston Facebook page, his Twitter page and the Instagram page. He'll check your smartphone when you board to confirm you've liked his social media pages.

McKinney takes donations from the public and sponsorships from local realtors and businesses to keep the tours free or low cost. If you'd like to make a donation, visit his GoFundMe page.