Hack Club’s Chris Walker and Castle Bravo

Education Maker Faire
Chris Walker of Hack Club

Chris Walker dropped out of Dartmouth and became a Thiel Fellow in 2013.  He had an idea for a math video game that was inspired by the TI 84 graphing calculator.  He tried creating an educational video game studio but it didn’t work out.  He joined Hack Club, a student-led educational intiative that started teaching coding but has branched out.  Hack Club’s founder, Zach Latta, was also a Thiel Fellow.  He worked with students to launch a new web version of the math video game called SineRider, which can be found at SineRider.com.

Chris started Castle Bravo as a personal project — with the idea of turning a bouncy castle into a boat — a motorized floating bouncy castle.  He’s now working with young people to create a solar-powered version.  Chris will bring the current version to Maker Faire Bay Area and we hope to see it on the Napa River at Mare Island.

Here are some photos from Hack Club:


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Dale: Before we begin, I want to remind you that Maker Faire Bay Area is coming up for two incredible weekends on historic Mare Island in Vallejo. The dates are October 13th through 15th and the 20th through the 22nd. Fridays are student days with a lower ticket price. Maker Faire Bay Area is back and it will be awesome. I hope you will join us and bring your friends and family. 

You know, one of the reasons, the idea for maker fair came to me was that I was meeting makers by starting Make magazine in 2005. I found them fascinating people, enthusiasts all, and I loved learning about them, learning from them and learning more about what they do and why they do it. I wondered would other people like to meet them and talk to them, as I did. Maker Faire started as simply a conversation with a collection of makers, an opportunity to find out more about the amazing things that ordinary people do, because they love doing things and making things. 

This interview with Chris Walker is a great example. Chris is a fascinating person, only 30 years old. He’s not a celebrity or an influencer. He doesn’t have a corporate title. He’s a maker and you’ll enjoy getting to know him much as I did in this interview. 

Who else do you know that sat on a bouncy castle and decided to turn it into a boat? So come out to Maker Faire and meet many more makers, see what they do, and you’ll be inspired. I hope to become a maker yourself. 


I want to welcome Chris Walker to MakeCast. Chris, tell us a little bit about yourself. 

Chris: My name is Chris Walker. I am 30 years old and I have been working for an institution called Hack Club with the Hack Foundation for about six years now with a little bit of time off in the middle there.

 I originally got involved in this wonderful group because I came out to San Francisco to do a program called the Thiel Fellowship which is Peter Thiel’s kind of, at the time, very audacious statement about the value of college and the peril of college debt and so forth.

Dale: So you were a Thiel Fellow in that? 

Chris: Yes. Yeah. Yeah. 

Dale: What year was that? 

Chris: In 2013. 

Dale: About 10 years ago. 

Chris: 10 years ago now, which is crazy. It feels not that long ago, but at the time, that was kind of a controversial statement about college and it has since become a mainstream view.

So for all of the other things that maybe Peter Thiel doesn’t get right, he got that one right. I was originally working on educational software, educational games, basically. That’s where my heart really lies. I’m just really interested in how digital systems can either with the assistance of teachers but mainly just autonomously really enhance the experience of someone who is a self-motivated learner.

I was really inspired originally by my TI 84 graphing calculator which was a formative experience for me in high school. I had this device, which was required to have for math class and I learned more from the calculator than I did from anything that I was required to have the calculator for and just from the process of plugging in functions to see, what the curve would be and learning about function composition that way.

That got me inspired around just like the potential. I also got into video game development generally then. I was making first person shooters and standard fare at the time, but I got into puzzle games because of Portal and because of the developer commentary from from the folks at Valve and and then that kind of just, a few things connected in my brain and I started thinking. Actually the first one was a game about voting systems, but just generally about how digital systems can teach and so I applied to the Thiel Fellowship to do that and I built a game called SineRider.

Dale: This is after high school, you apply for a fellowship, right? 

Chris: Yes. I went to Dartmouth for one year. Realized pretty quickly that wasn’t for me. I dropped out of college before I knew what the fellowship was to start a game studio. The game studio wasn’t supposed to be an educational game studio.

It was just with some co founders from school. I kept trying to make it be an educational product for my own personal reasons, and so the studio didn’t go anywhere, partly for that reason, but also just because, I don’t know, game studio is really hard.

 I ended up applying for the Thiel Fellowship instead, and I got that, and that was obviously a big life-changing event. I moved out to San Francisco, and I built SineRider, which is this game about function composition, and it was inspired by the TI84 Graphing Calculator, and it’s a game where you use functions to solve puzzles. That was my attempt to build a game that was –I promise this all ties back to Hack Club– but that was my attempt to build a game that is not just a superficial gamification of mathematics, but actually where like a series of puzzles where the mathematics is deeply intertwined with the mechanics of what you are engaging with in the game. You can puzzle through mathematics the same way that mathematicians do, but with all the trappings of a well designed game around it.

So then that project I just ended up having some very inspiring conversations with another Thiel Fellow Zack Lat ta who founded Hack Club and he was class of 2015 in the Thiel Fellowship. Then we went our separate ways for a number of years, and I worked for a startup and just tried to make math games a career in various ways and didn’t. It’s a very… I would say it’s a tough industry, but it’s not really an industry at all. 

Educational games, there’s all kinds of market reasons why they don’t really exist in a marketplace. Eventually Zach called me or I was talking to him at some point. I just quit this job and he was just like just come work for Hack Club. We would love to have you.

I ended up working there doing a lot of administrative things for a while and then years later, we actually just decided what if we took SineRider and turned that into a student project. So this is how it all ties in is that over the last year we took SineRider with a bunch of my students and took an old prototype version for a web, like a JavaScript native version that I had off the shelf from a couple years ago. They took it from 50 percent to 100 percent and did all the art and music and graphics programming and everything around it.

Dale: And that’s available? 

Chris: Yes, Sinerider.com. It’s a free game and we’re trying to get it in every math classroom in the world. But that’s how it all ties together and what I’m doing right now is taking things like that and doing really awesome projects with my students.

Dale: Hack Club is an afterschool club? 

Chris: It’s whatever you want it to be. Our thing is student-led. We are the world’s largest network of student-led education initiatives. So we don’t work with teachers or school districts or principals or parents or anybody, but we only work with students who find us. They might want to start a coding club. That’s the Hack Club program. That’s our core thing that we started with, but we also facilitate hackathons and student magazines and grant programs and big kind of headquarters projects like SineRider or Sprig or Operation Castle, that’s the bouncy castle. So Hack Club is largely a network of coding clubs. It’s a worldwide network. There’s thousands of them around the world but it’s also a broader thing, just anything that you want to run as a student-led education initiative, we will support.

Dale: It’s not just digital or coding related, is it? 

Chris: It definitely started there and that’s the easiest thing to do if you’re going to do a student-led program since we started as a small scrappy organization and coding is the thing that you can teach for free since pretty much everybody has the resources to learn it if they have a computer or even a phone.

But we’ve really expanded more. I’ve tried to push really hard on just making it, just building things generally, being creative. It could be creative writing. We have a huge active art community. We have students who are really into music or HomeLab servers, or so it’s all kinds. 3D printing is really big for us too.

It’s hack, hack as in hackerspace or hackathon and anything that you can put under that umbrella, we’re pretty into, but it’s a really big tent group. So there’s also all kinds of random things that run under our org that like, are just like– you might not expect. 

Dale: We ran into each other because you applied to bring your boat project to Maker Faire Bay Area. I’ll let you explain it. 

Chris: Yeah, of course. So the project is called Castle Bravo. Full operation is Operation Castle. Castle Bravo is a self-propelled motorized, floating bouncy castle and it’s a project that I originally did earlier this summer as a personal project just cause I thought it would be really fun. I was sitting with some friends on a bouncy castle and we started talking about how funny it is that this thing is so big, but would float very well.

And we did a little bit of math and just estimated, there on the castle, that it’s wow, okay. Roughly, we’re talking about like 10,000 pounds with the buoyancy here. You can put a lot of weight on this thing. And so then we just kept talking about, okay, but how would you actually, like, how would you power it?

Cause bouncy castles have to be continuously inflated. And how would you keep it safe so that if it loses power or pressure, it’s not gonna collapse on everybody and kill them by drowning them. It’s this big netted enclosure. We kept talking about it in the morning. It still seemed like a pretty good idea and so we bought a bouncy castle for about 600 bucks on Facebook Marketplace. Then I took that to an event called the Ephemerisle, which is a Burning Man style event on the water where everybody brings a bunch of docks and boats and homemade floaty things and ties them all together into islands. It’s a big party out there for a week. When I came back from that.. 

Dale: Where is that event? 

Chris: That’s in the Sacramento River Delta. It’s seven miles away from the marina. So we had to drive the castle out there with a little outboard motor on it, which was a whole crazy adventure of itself.

So my students were not involved at that point, basically because I wasn’t totally sure if I could do it safely. That was just a fun thing that I did myself. But afterwards I started thinking like I really want this thing. My big problem with it is that it’s just powered by dinosaurs and I hate burning gas for anything.

Unfortunately I do a lot of projects — I do a lot of fire art, actually, among other things, where it’s like burning gas, burning propane, burning methanol, burning diesel, whatever. It’s all part of it, but I really want something like this to be a solar electric system, partly because then it’s the fuel of the future. But also the thing about having a beautiful castle on the water and floating around on it is that it’s so magical. Except for the loud brrrr of the generator and the brrrr of the power cord motor and it ruins the magic to be sitting on this thing and have these horrible noises all around you. So I really wanted to be solar electric so that it can be silent and magical. So I thought, all right I know nothing about electrical engineering.

I know how to make video games and I know how to build bouncy castles and do steel and wood fabrication and stuff. I don’t know anything about robotics. I don’t know anything about electrical systems, but a lot of my students do because they’re involved with robotics clubs or designing their own circuit boards. I have a lot of really smart kids. So I thought, all right what if I take it to them and we’re just going to come up with a plan for doing a solar electric conversion, which is not going to be ready for Maker Faire. For Maker Faire, it’s going to be dinosaur powered. We’re hoping for Maker Faire next year, we can have basically the whole thing.

There’s all these different layers to it. There’s like the motors that power the castle and the motor controllers and the 24 volt electrical system that is going to have to run the whole thing. That is a lot of power to move an object that large; it’s 12 by 24. And it’s not particularly hydrodynamic.

It’s a high power engineering system. There’s the electrical control system to steer it and you might have a little app to control it, or you might do a logic controller.

Something that we would like to do eventually is make it remote controlled and have that be something where we can control it from our Slack channel and make it like a Twitch Plays Pokemon kind of thing. I think that would be a really fun way to drive it around the water. We’re going to put a sound system on it, signs, probably a big train horn, and all these things have to be computer controlled.

So these are all things that students from all around the world can participate in the engineering of. And then there’s actually a headquarters — my students our headquarters is in Burlington, Vermont. I live in California some distance away. But we have a bunch of students who are there for basically doing gap years, which is something that we do with students that have reached a level of seniority within our organization.

Those students are building a mini castle right now. And that’s a whole other set of engineering problems. How do you scale it down? How do you make sure, that’s basically our way of doing a slightly less expensive version of all the control systems first.

And then we have some other students out here who are then going to mirror all of that stuff on the big version. So it’s just turned into this big community engineering project. And anybody who wants to be a part of it can be a part of it. Cause the great thing is that I have no idea what I’m doing. My job is pretty much just to provide direction and like insight on the craft itself, but it really is like a student driven project. 

Dale: Where did HackClub start? 

Chris: In Los Angeles in about 2015 because that’s where Zach Latta was in high school.

He dropped out of high school or tested out rather to found the organization. And then he got the Thiel Fellowship and he moved to San Francisco, which is where it was headquartered for a number of years. During the COVID years, it moved out to Burlington, Vermont.

Dale: I look forward to seeing the Castle Bravo at Maker Faire in the Bay Area. Let me ask you, do you think it was the right decision for you when you dropped out of Dartmouth. Did you get the equivalent things you needed from the Thiel Fellowship and just going on your own?

Chris: Yeah, so I do think it was the right decision. I’m very happy with how everything turned out, so I have no regrets about it. I also think that this is one of those things where, at least for me, I think there is a little bit of a self congratulatory narrative in Silicon Valley around the dropout culture sometimes where it’s yeah, we were too smart for these institutions, basically, and the truth is that for me, I was just depressed. I was depressed because I don’t think the institution was a good fit for me.

I got pretty happy once I was working on things that were more satisfying. I just would never really frame it as a choice. It was something where I got there and I just found oh man, like I have all these projects and I can’t get school credit for them.

There are all these really cool professors, but I have I have questions outside of class. They clearly don’t really have time or institutional incentives to help me out with my obscure computer graphics mathematical rendering project or whatever. Then at the same time, it’s oh, my God, this place costs like $60,000 a year. Holy crap. So the combination of these things just left me feeling pretty sad about the situation.

When I left, it was definitely a crazy risk and I don’t know how it would have turned out if I hadn’t heard about the Thiel Fellowship or if I hadn’t gotten in. On the one hand, everything turned out great. On the other hand, there’s no denying it was a crazy risk. I dropped out before I knew what the Thiel Fellowship was. I really didn’t have much of a plan. 

I was going to do a game studio, which didn’t work out. And I don’t know. It’s really hard to say because the counterfactual of what would have happened without this like crazy non replicable event of a billionaire saying, yeah, here’s a hundred thousand dollars is pretty hard to analyze. But at the same time yeah, if I were to do it all over again, I would do the exact same thing. 

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DALE DOUGHERTY is the leading advocate of the Maker Movement. He founded Make: Magazine 2005, which first used the term “makers” to describe people who enjoyed “hands-on” work and play. He started Maker Faire in the San Francisco Bay Area in 2006, and this event has spread to nearly 200 locations in 40 countries, with over 1.5M attendees annually. He is President of Make:Community, which produces Make: and Maker Faire.

In 2011 Dougherty was honored at the White House as a “Champion of Change” through an initiative that honors Americans who are “doing extraordinary things in their communities to out-innovate, out-educate and out-build the rest of the world.” At the 2014 White House Maker Faire he was introduced by President Obama as an American innovator making significant contributions to the fields of education and business. He believes that the Maker Movement has the potential to transform the educational experience of students and introduce them to the practice of innovation through play and tinkering.

Dougherty is the author of “Free to Make: How the Maker Movement Is Changing our Jobs, Schools and Minds” with Adriane Conrad. He is co-author of "Maker City: A Practical Guide for Reinventing American Cities" with Peter Hirshberg and Marcia Kadanoff.

View more articles by Dale Dougherty