Kids And Hacking: Electromagnetic Eggs

One of my favorite things to do is visit with school kids who are interested in engineering or science. However, realistically, there is a limit to what you can do in a single class that might last 30 to 90 minutes. I recently had the chance to work with a former colleague, a schoolteacher, and The Teaching Channel to create an engineering unit for classroom use that lasts two weeks.

This new unit focuses on an egg drop. That’s not an original idea, but we did add an interesting twist: the project develops a “space capsule” to protect the egg, but also an electromagnetic drop system to test the capsules. The drop system allows for a consistent test with the egg capsule releasing cleanly from a fixed height. So in addition to the classic egg drop capsule, the kids have to build an electromagnet, a safe switching circuit, and a test structure. Better still, teams of kids can do different parts and integrate them into a final product, closely mimicking how real engineering projects work.

There are a few reasons for the complexity. First, given ten class sessions, you can do a lot more than you can in a single day. Second, I always think it is good if you can find exercises that will appeal to lots of different interests. In the past, I’ve used robots and 3D printers for that reason. Some students will be interested in the electronics, others in the mechanics, and still others will be interested in the programming. Some kids will engage in 3D modeling (robot simulation or 3D objects). The point is there is something for everyone.

Drop Control can be a Class in Itself

aldest600Not only does this diversity help engage students, but it also offers many teaching opportunities. You can easily use the system as a springboard to discuss different types of force and energy (electrical, electromagnetic, gravity), for example. The switching circuit can be a simple SPST switch, or it could be a complex system with a safe switch and even indicator lights. It doesn’t have to be very complex. My prototype used a few bucks worth of switches from Home Depot (see left).

In fact, although you can make things as complex (and as expensive) as you like, it doesn’t have to cost much at all. A budget-conscious school could use zip lock bags as the capsules, tin can lids for magnetic attachment, homemade electromagnets, and forego the switches for a direct wire to the battery. Or, you could let your Arduino class create a complicated fire control system.

To change the emphasis of the exercise, you can tune various parts of the project. For example, you can assign different pieces to different classes or groups and have one group that integrates the final product. The teacher can provide complete parts to deemphasize those portions. For example, a ready-made test stand or an electromagnet can make the project shorter or easier.

Learning About Design Decisions

As you can tell in the video, Tony Castilleja and I have a good time working with the kids. As they design the parts of the system, I like to discuss design trades: the balance of cost, weight, power consumption, and other factors to decide what design choice is “best.” They never fail to surprise me with their creative solutions. We’ve seen cushions, parachutes, and even seat belts. As designers, we take it for granted that “best” doesn’t necessarily mean anything without context. What’s the best kind of truck? The answer is different if you are hauling gasoline instead of chickens. Exercises like this one help future fledgling engineers get that same type of insight.

It also can improve your communication skills. One thing we tried to get the kids to do was to produce drawings before they built things. My old drafting teacher (Mr. Stewart) always emphasized how you had to have enough dimensions on a drawing that someone could build the thing. If you had too many dimensions, he might mark off a few points. But if you didn’t have enough, you were getting an F. It surprised us, however, when some of the kids drew their boxes, measured the lines on the paper with a ruler, and dutifully wrote down the measurement of the line on the page! It surprised us, but it shouldn’t have. It was an entirely understandable interpretation of our instructions unless you had the background that we all have.

The Teaching Channel does an excellent job providing course material (under creative commons) like this to schools. If you browse their video section, you’ll see they have many similar modules. The real unsung heroes, though, are the teachers like Destiny Woodbury (seen below, on the right). The amount of extra time they put in to make sure these future engineers get hands on experience is nothing short of humbling.


Last year, I posted about a very abbreviated version of the egg drop that I do when I just have an hour with the kids. Although it isn’t as involved, they still have fun, and I can still work into my design trade talk. In that case, their selection of materials drives their weight and cost but still has to be effective. With either project, you can even put the A in STEM, and have students decorate the eggs, the capsules, and the controller boxes.

The video below is kind of an overview of what the unit is about. You have to visit the Web site to download the supporting materials, if you want the actual materials and notes.

I’d encourage anyone with enough interest in technology to read Hackaday to get involved either with outfits like the Teaching Channel or just with your local schools and teachers. The cost to you is small, and the rewards can be very high. To quote from the video, one of the students told a teacher in another class “This is the best day of my life! I’m going to be an engineer!” You can’t put a price on that.

Thanks to Tony Castilleja, Destiny Woodbury, and the rest of the team who worked on this unit (especially last year’s class at the KIPP Liberation middle school).

24 thoughts on “Kids And Hacking: Electromagnetic Eggs

  1. “A budget-conscious school could use … tin can lids for magnetic attachment”
    Only if you don’t factor in the costs of first aid, or time spent writing accident reports and explaining why you chose to use nasty sharp metal instead of something safer…

    1. I find this issue to be self limiting and another great opportunity for safety education. A can lid is no more dangerous than a pair of scissors, something I would expect students at this level to be capable of understanding, otherwise you might want to change your curriculum. As a freshman one of my teachers liked to have his class make “rock music” his euphemism for percussion flaked arrowheads and knives made from obsidian (one of the sharpest substances you will EVER encounter). Quite frankly I was amazed the school let us do this on school grounds in a classroom.

      1) It’s Sharp, you can pretty much cut anything worth cutting nearly instantly with an obsidian flake
      2) You’re making weapons at school, every flake is a potential weapon/injury
      3) I didn’t think it would ever be relevant but you would be wrong
      4) It was FUN and EDUCATIONAL

      Turns out there are entire college classes in “Lithic Technology” and frankly our ancestors had some DAM good ideas, just reachers the “Addle Addle”

      Don’t sweat the small stuff, worring about a tin can lid is why schools have issues teaching student relevant concepts

    2. We worked in class with metal sheets at age 12, soldering irons and other dangerous sharp things/tools. It’s how you learn to respect tools and materials and how to handle them in a sensible way. Kids that grow up in a bubble are a danger to themselves cause they can’t calculate the risks. Sure I cut, burned and pierced myself but it would’ve happened sometime probably and young skin heals easier :) :P

  2. Far out great for you yo volunteer Al, good work. Strange thing is that I read this when I did Earkier I drove by whereI attend elementary school and was remind I should contact them volunteer to be what wasn’t available hen I was attending. A resource for students to contact when they had question that where electoral, electronic or mechanical in nature. When I was attending thar school it was in the 1960s and the school never had any instruction separate fome anything else and was called science introduction There weather only a few general assemblies where the student gathered in the cafeteria to watch a film. The only one I can remember is a film on the Weather and t how that started a life time interest in the weather. On reason I haven’t gotten a hurry is that the school is a Catholic parochial school, and for a varity of reason I became distant from the parish and organized faith in general. I would so more abou that but refrain because I’ll link to this in the email I plan to send to that school offering to volunteer to be an “Elmer” in using ham radio slang. I would be interested in seeing mor article of this nature. Ladies an gentlemen of Hackaday.

      1. One thing I love about Hackaday is the lack of upboats/votes/swags. While comments like yours are funny, amplifying them simply does not make sense in the context of the site’s system.

  3. If every person with technical skills did this it would make a very big difference to the level of interest in STEM, in fact I’d go as far as to say that such a grass roots movement would have a greater impact than anything a government could afford to do.

      1. Huh? I’m not talking about teachers, I am talking about people with industry experience taking the time to share it and inspire kids to be enthusiastic about following a STEM pathway, because the truth is if you have enough passion for something your circumstances are far less relevant to the question of if you will be successful.

        1. Yeah, it would be nice if every tech person could do this. But the administrations have set it up in such a way that teachers either don’t have time to bring in outside educators, because “no child left behind” requires teaching to the test each quarter, or they require that even outside assistants have a teaching degree.

          I worked on a project in university that was designed to blend a bit of music and art education in with some excuse to get kids physical exercise during class time. For older students, the code to the project was also available so they could change visuals, or implement different music (I left lots of notes in the code about “this is how this value works, change it this way to do this, or that way to do something else”). What happened, though, was that teachers just didn’t have the time to implement lesson plans based on this; even after they attended a conference and picked to work with our project. So we had to have a lesson plan available for them, that they could get approved by their administrators, before we could even set foot in the schools. In the end, we had 30 minutes with a bunch of young kids to get them moving and dancing and learning about art, and maybe 45 minutes with high-school students discussing how Jackson Pollock changed art. We couldn’t even leave the code with them, because that didn’t meet the “art class” curriculum.

          If your school lets you volunteer, please do it. Otherwise, volunteer at after-school programs or open-universities, and vote to get rid of the “teaching the test” requirement that bases a school’s budget and teacher’s pay based on what percent of their kids pass a nation-wide standardized test each year.

        2. I believe Timgray1 was saying that school administrators won’t stand for STEM volunteers coming into the classroom to teach students useful things, because that implies that the normal daily curriculum is effectively useless. Administrators/managers never like it when they have ‘earned’ lifetime employment, and some random guy walks in off the street, and does a better job…

          Nevertheless, it should be done. Kids need to learn how things work ‘in the real world’, and schools are doing such a terrible job.

          1. Tue, for many teachers it is the first and only career they have ever had so there are huge gap between what they know and how industry and commerce function. Volunteers would be an ideal way of grounding the educations system more solidly in reality.

    1. Unfortunately, it seems you haven’t been introduced to many intellectually curious students. Calculus, mathematics, and “boring things in science” are my favorite part of being alive, and I’m not some random bingo-playing autistic bean counter (uptick in autism diagnosis is just the new anti-intellectualism to me). The way I see it, engineers and scientists are magicians, physics is magic, and everyone else is a bunch of Muggles that don’t know why their flying cars even work.

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