fiziks_hckr

I've taught in schools from all corners of San Francisco, and can't agree more with majority of what was said in this article, except maybe the money part*, I'll leave a footnote for this.

One day when I was volunteering at one of these schools, a student came up to me showing a picture of a robot how cool it was. When I mentioned that it was relatively easy to build, he got super stoked, told his friends and before you know it, we had a class of 8 students pursuing their own interest, learning CS/Breadboarding/Electrical-Circuits, all student driven, building cardboard-box arduino-based robots afterschool.**

These student led classes were majority black students and pushed forward most by black students. Everything was honestly instantly working great, and at the end of every class my students made to promise not to forget to show up to the next session (I don't recall missing a session, I believe this was out attachment for the course).

Self-driven learning is a thing, and all we have to do is give kids grounds to explore -- in this case to create designs from from their own imagination (ey, isn't that why we're hackers here : D? We can all relate).

* Small class sizes help (or student:teacher ratio of 6:1 ideally). This is the ratio (lower works too) that really works, and I've seen only at really rich schools (see Branson/UHS/Lick Wilmerding) and programs based on it. I've seen this emulated to great success in Summerbridge SF, and too at a summerschool I helped start in the bay area based on project-based/student-led learning, access to technology, and most importantly these small class sizes that enables hosting these free-learning classes.

**Again money is important, materials costs for this class were supported by my concurrent 4 jobs, doing mainly part-time engineering work for startups, electrical-engineering curriculum development for a summer-schools, as well as tutoring.

Math not necessary being about numbers but concepts is something I'm really happy to see : ) in sibling comments on this article in HN.

Ive been hoping to find others interested in this vein of xrf for community lead detection would be more thab happy to connect.

well icp (inductively coupled plasma) is the gold standard (expensive but highly sensitive and used for heavy metals like lead in stuff).

xrf can spot higher concrntrations, but one can concentrate beforehand and then use xrf. while xrf fixed cost is 30k usd its cost is a dropjn the bucket compared to icp and solid state keeps on going.

forgive my typos commenting via phone

From my experiments making my own, got around 100W of power.

For reference, a laptop is around 30watts, charging a cell phone around 5w, electric shavers, fans for air circulation, small monitors are also game, so there are things you can power.

Storage can be achieved with a blocking diode and a supercap, or more conventional easily obtainable battery charging circuitry.

The article wanted to use these as supplementary power, and so during an emergency wouldn't be far fetched for bike-power to be useful.

That being said, for sustaining refridgerators (always on), or for using large power draw of washing machines, dryers, and microwaves, one would definitely need to rely on more than just biking (e.g. stored wind or solar as you pointed out).

But again, bike power can be useful as a backup or for emergencies.