Lockpicking in Computer Science


I picked up a new hobby at Defcon this year. It turns out that there is a lot of crossover between the lockpicking and hacker communities. It looked so fun I thought I had to give it a try. And when I began talking about security in my computer science class, I picked a lock as an illustration of a point I was making. I’m not sure if the point was received or not, but the kids were VERY interested in the lockpicking! So of course that became a carrot. If we could get through the material in hoped to get through, I would show them how it’s done. A couple weeks later, I found the time to try it during a study session. The kids went nuts for it! Well over half the class managed to pick a simple padlock over the next couple of days, and some of them have stuck with it. I’ve had at least three pick standard home-use five-pin tumblers (inspiring me to up my own game!), and I’ve heard from a couple that they have ordered their own picks and practice locks already.

I’m not aware of lockpicking being on the curriculum at any school. And I’d be hard pressed to justify adding it. But I’m a strong believer that if the kids are passionate enough about something to spend their own time learning it, then it is well worth the time to support that.

It’s really difficult to tell what will excite a particular child, and sometimes the most unexpected things will become fads. When my own son attended this school, a teacher introduced him to the Rubix cube. It became his obsession for a couple years. He spent countless hours researching and practicing, and finally achieved a time of around 20 seconds. All of this was completely on his own. This knowledge will probably not get him ahead in life, but his ability to learn on his own and become passionate about it certainly will.

So while I’m really excited about teaching the kids as much computer science as I can manage to pack in, and while I’m convinced that they can’t get enough of reading, writing, and math, I’m really glad that I could spend a few hours on something that might be completely impractical and not on any standards. Because sometimes, that’s where the important learning happens!


Final Breakout activity

I finished off my computer science unit with a breakout activity that I thought went very well. I broke each class into four-person teams, and game each of them a locked box. The only clue on the box was a long string of 0s and 1s I attached with a label maker. The students eventually figured out they need to translate the binary into ASCII, which gave them the combination to the lock (the first class actually figured out they could get the contents out of the cheap Harbor Freight box without actually opening the lock. I fixed this later by packing more stuff into it!). Inside the box was a hard drive, with a sticky note challenging them to guess the password. It also contained a decoding wheel, which we’d used doing ciphers earlier. The students installed the drive into a computer (computers were conveniently stashed nearby) and attached all the peripherals. When they boot it, they were met with a password screen, and had to guess. This was the trickiest part, since all the groups were trying to decode random things to find a password. I’d hoped they’d get my earlier hint and try to actually guess common passwords, which they eventually did.

The only file visible on the computer screen was a secrets.txt file, which contained a ciphered text and a cryptic clue the students needed to google for the key. This went very smoothly, and almost all groups were able to decode the Vigenere cipher pretty quickly (a victory for me, since I’d tried unsuccessfully to teach it in the past!). The cipher instructed them to find another searchable piece of information, and deliver it and a flower to the front desk. I was just curious to see how the groups would handle the flower. Some picked one outside, one group brought a flower-shaped pen. No one thought just to draw one. Once everything was delivered, each group member got their 3D-printed “I Survived Computer Science” medal.

I got lucky in that the activity took up about the right amount of time. The last group finished with about ten minutes left in the hour-fifteen minute class. That left just a bit of time for clean-up! When I surveyed the students, later, they said this was one of their favorite parts of the class, so I’ll definitely be trying it again. 6-cs-final-project