As bad as the prior story is, I don't know if intentionally misleading the students is the right way either— what if one had realized the contamination and acting in good faith had cleaned out the bottle? What if they did this afterward and ended up redoing the experiment only to be told they had cheated?

I'm all for exposing students to something unknown, but telling them they're doing X when it's really Y for anything longer than a single lecture ain't it.

You can square that circle by announcing at the beginning of the course that there is going to be some assignment like that, but I'm not telling you which, because the real world doesn't.

I do agree this is a good point; trust is not something that should be simply squandered. Nevertheless, this is still a lesson that needs to be taught and so often students make it to the end without a single teacher that did.

This is ambitious. I once had a college class where the students were very upset because I decided to change the number of in-class quizzes from 5 to 4 a few weeks into the course. (The quizzes made up 10% of the overall grade.) Students hate it when you do anything even remotely weird or unexpected with assessments. Telling them that there is going to be a mystery trick assessment will just make them anxious and grumpy.

Right but doing it without saying anything is much worse.

Given that a report is supposed to tell what you did and then your calculations and conclusions, you'd better include something as dramatic as “we washed the equipment after getting the wrong results and detecting contamination”…

If you detect it and think it's relevant, that might be worth a note. But "reset and start over" is something that could reasonably be thought of as outside the scope of the report. You're reporting on the experiment, not logging your entire time in the lab.

That would be a very valuable lab, IF students hadn't been explicitly trained in opposite behaviour for a decade by then.

I lived a very similar experience:

My 4th year computer science professor in software engineering assigned us a four-phase programming assignment for the semester.

My teammate and I spent several sleepless days on the first assignment, and felt some of the requirements were contradictory. Finally we reached out to the professor, and he formally clarified the requirements. We asked him, "well OK, if requirements are unclear, what are we as students supposed to DO?!?" and he answered - exactly what you did; ask the user/client for clarification. "OK, but what if we hadn't, what if we just made assumptions and built on those??". And his eyes twinkled in a gentle smile.

My team mate and I had worked in the industry as summer students at this point, and felt this was the best most realistic course university has offered - not the least because after every phase, you had to switch code with a different team and complete next phase on somebody else's (shoddy, broken, undocumented) code. This course was EXACTLY what "real world" was like - but rest of the class was trained on "Assignment 1, question 1, subquestion A", and wrote a letter of complaint to the Dean.

I understood their perspective, but boy, were they in for a surprise when they joined the workforce :)

>That would be a very valuable lab, IF students hadn't been explicitly trained in opposite behaviour for a decade by then.

I teach students sometimes. I briefly considered whenever I should give them such important lesson. Very briefly: my job is to teach students my specialty, not give them life lessons. Why would I deal with potentially angry students for doing something that's not obvious I'm allowed to do? Hell, it's not even obvious it that would be a "good" (career advancing) lesson.

Being in a professional field means being the expert in the room for your area of responsibility. That means being able to translate information into, and out of, the terms of art in your profession.

This is generally considered a "soft skill", but it really should be a recurring part of any technical curriculum.

There are generalizations of the concept- tailoring your message to your audience in public speaking, or charitable interpretation and seeing from another's perspective in debate, but the narrow case of "interpret these requirements and identify problems with them" is a good way to demonstrate an understanding of the domain.

I agree, that's a valuable skill. But do I, an expert in a narrow (very far removed from any soft skills) field, am the person who should teach it? When some students raise a complaint, how will I explain to the University management that this twist, even though completely unrelated to what I am supposed to teach, was actually a good idea?

I just say, even with good intentions, the incentives are not aligned with teachers going too far out of line.

In one class I took, we were examining a range of car engines for faults and the task was to get it running.

The rumour was that the previous years class had one engine where the ignition rotor arm wire had been replaced by section of coloured plastic which was covered in the usual grease and crap in the housing.

The instructor was looking for persistence and elimination of possibilities rather than actually solving it. But one team did. As long as you solved the others that was enough to complete the class.

Even as I rather vigorously grumble at the status quo, let it be noted that I celebrate those iconoclasts fighting the good fight all the more for the fact that they are going against the status quo to do so. May their tenacity and creativity ultimately prevail.

The trouble with these kinds of games is that they put the more diligent students at a disadvantage. For example, someone might compare their experimental result against the textbook constant, realise it's wrong, and spend much more time trying to identify their "mistake", not realising they've been sabotaged. This puts further pressure on their other work.

One cannot argue that this is fair on the basis that it's the "real world", because all that does is reward the sloppier (middle) approach. It filters the very lazy from the average, but at the expense of the excellent.

Given that the labs were with TAs present, at that point, you'd just go to the TA and they'd tell you to write down the number even if it didn't match.

Not only that, but an appropriately diligent student might notice with their eyeballs or nose that their bottle contained alcohol, and clean/dry it before performing the experiment.