The first time was the summer between second and third grade, when I had to go to summer school because I couldn’t remember my multiplication tables. The second time was when I had to go to math lab in 8th grade because I still couldn’t do long division. Oddly enough, I was one of the few kids in my school reading above grade level.
My senior year in high school, when I simultaneously struggled with Calculus, AP Biology (actually I did very well in this class, but I never could memorize the amino acids), and Honors Physics. The serious case of “senioritis” I had that year didn’t help, either.
About those amino acids – I even made myself a set of flashcards, with the molecular schematics and chemical formulae – but to no avail. Apparently my brain is impervious to any symbolic representation of amino acids and will accept them only in their natural form, supplied preferably from unnatural, overly processed foods. 
When MENSA called my dad ,apologised and explained to him,that they called the wrong guy, due to a errror in their database …
First week at MIT. In high school I’d aced every physics problem set and exam, pulling the highest grades in the class. I boned up on my Calculus (since we used the same text as MIT – George B. Thomas’ book) during the summer so I could Advance Place out of first semester of Calculus at MIT. They had a deal where you could get out of the course if you could pass all six of the course exams, so I set out to pass them during Residence/Orientation week, before classes started. I got through the first one easily enough, but it took a couple of tries before I got through the next two (you got three chances to pass), and I only got through the last one by the skin of my teeth. I decided not to try to do the same with physics.
Which was just as well, because I did so poorly on the physics problems that I actually had to go to the weekly “remedial physics sessions”, where i REALLY learned my freshman physics. THAT was a comedown – from top of the class to remedial help, in one step. As grafitti at MIT eloquently put it, “MIT is a great place to learn what it’s like to have an IQ of 100”
This happened to me at Caltech; I’d been accustomed to breezing through classes with minimal work and being one of the top people in my high school, but then I went to the place where all the valedictorians went. These people were smart, and they studied like hell, and I was below average for the first time in my life. That was really tough, and I stayed below average for the five years it took to get my BS. I was very humble by the time I graduated.
When did you realize you weren’t as smart as you thought you were?
1.0 When I stopped hanging out with high school drop outs.
2.0 When I started hanging out at the SDMB
Thanks for starting this thread!
For me, first quarter in college. I was always considered smart, tested well, etc. I got myself admitted into a reasonably prestigious school. When meeting with my adviser to choose classes, she recommended I take a foreign language. With a large amount of hubris, I chose Middle Egyptian Heiroglyphs.
Wow. That was the first time in my life I ever felt really, really dumb. I would study and study for hours a night, and get D’s (or worse) on homework assignments and tests. I just could not grasp it. It didn’t help that I was the only undergraduate student in the class, but I realized I had finally reached my limits, and it caused me to seriously reevaluate my opinion of my own intelligence.
Of course, then I started drinking, and I’ve gotten significantly dumber since then. 
Organic Chemistry I at 8am.
First year of undergrad at a well-respected university. Went from never really having to study or try hard to holy crap, you’re asking me what again? What does that even mean?
I found grad school pretty easy but the calculus, chemistry, physics and languages fairly brutal. Plus, there were no idiots, seemed most everyone was very, very intelligent.
My third year of being a physics major in college. I hit the upper level classes- or, rather, they hit me like the proverbial ton of bricks. I was just not used to putting in that much work on one class. There are various formulae for how much work you should expect to do per class- for every credit hour, you will put in X number of hours outside of class. I found that, no matter how many credit hours they were, one of those upper-level physics classes took about 20 hours a week. Two of them, which might only be 6 or 7 credit hours, was a full-time job in itself.
Then I got to grad school. I found out I wasn’t as good at astronomy as I thought I was 
I’ll take a swing at it.
Blackbody radiation is the radiation that everything gives off because of its temperature. It depends only on the temperature of the object, not on any of its other properties. It doesn’t matter what it’s made of, for example. People give off blackbody radiation in the infrared. If you have an electric stove (not a cooktop- one of the ones with those coiled burners), you may have noticed that the burners glow red when they are on a high enough setting, but are black when they are not- that red glow is blackbody radiation. It’s giving off blackbody radiation in the infrared when it’s off, but you can’t see infrared. The colors of stars come from blackbody radiation, so we know that blue stars are hotter than red stars (at least at the surface, which is all we can see of a star). If you measured the exact wavelength of that blackbody radiation coming from a human, a hot stove, or a star, you could plug it into a formula and determine the temperature of that object (this is actually done for stars).
Blackbodies don’t just radiate at one single wavelength, though. They send out radiation at a bunch of different wavelengths, but there is one wavelength where they send out the most radiation. The wavelength of this peak is what determines the color of a blackbody.
It’s called blackbody radiation because, in order to be able to determine the temperature of something from its color, you have to be sure that the color you see is the color determined by the temperature, not the color determined by something else. Reflection is a possible “something else”. Objects reflect colors independent of their temperature- someone wearing a blue shirt is not thousands of degrees hotter than someone wearing a red shirt. Something that reflects no light would appear black (if it weren’t emitting visible blackbody radiation), hence the name blackbody.
The “catastrophe” you were talking about is called the Ultraviolet Catastrophe (yes, that would be a good band name). In the early twentieth century, two physicists named Rayleigh and Jeans tried to use classical physics ideas of how electricity and magnetism work to come up with an equation that would show, as a function of temperature, how much energy a blackbody would radiate at different wavelengths. Problem is, their equation showed that, as the wavelength gets shorter, the amount of energy radiated at that wavelength should keep increasing, no matter what the temperature of the blackbody. According to their equation, all stars should be purple (or at least blue), which they are not. You can go out and check this if you are having better weather than we are today- the sun is neither blue nor purple (don’t look at it for too long).
If you came up with an equation that implied something like that, you’d think, “oh, I forgot to carry the two somewhere”. But they, and many other physicists, checked their work, and they couldn’t find the mistake. When something like that happens, according to the scientific method, something in your underlying assumptions must be wrong. In this case, it turned out to be the assumption that the classical model of electricity and magnetism is useful for modelling blackbody radiation. It isn’t, and you need quantum mechanics to do the job properly. This is a textbook example of how major advances in physics happen. People get Nobel Prizes for this sort of thing.
Okay, I just realized it again.
While I was pretty academically successful throughout school, I was never as smart or as good at anything as I wanted to be, so I don’t remember ever having a revelation. I was just always sad.
Haven’t entered grad school yet, though, so we’ll see!
Yup. In the real world, I’m the go-to guy for virtually any question anyone might like to ask. Here, I’m not even a blip on the radar.
Also, when I tried to understand the EPR paradox. I found out about it here when someone said it disproves determinism. Since I’m a staunch believer in determinism, I found this very interesting. So I read about it. Didn’t understand. I read something a bit dumbed-down. Still nothing. The EPR paradox for dummies. Nope. The bleeding Wikipedia page. Eyes glazing over after a few paragraphs.
So, here I am, previously believing in strict mechanistic determinism, now plagued with the knowledge that there are really, really smart people who claim that the EPR paradox disproves strict mechanistic determinism, and I can’t even have an opinion about it as I can’t understand it in the first place. Even worse, I can’t understand how anything could possibly disprove determinism, even hypothetically.
College.
I had a choice to go to college A where I would be in the top 10 percentile or college B where I’d be on the same level as everyone there. I chose college B because I thought I would be happier, compared to college A which looked like just running through another 4 years of high school.
I’ll be honest, I’m always stressed and at my wits’ end here. I feel like I know nothing. I consider it a good day if I can retain a fact and regurgitate it on a test later on. I always feel like a slacker compared to the girl next to me who is in every single organization and can memorize any text she reads.
College has totally humbled me. This isn’t to say that I thought I was a big shot in high school or anything, just that it made me even more aware that there will always be somebody smarter than me, and I’m just not the brightest cookie in the shed. But I am grateful for coming to this college and I would relive it all over again if I had the choice.
That’s why they schedule it then.
I never felt dumb in those lectures. The lectures made sense, the concepts were clear, the problems in the text all made sense [and I did all the problems in the texts, because of that little problem with highschool chemistry]. Nope, never felt dumb in class.
If the professor hadn’t graded on a curve, I’d be a biologist today. I could not do his tests.
I had a girlfriend like that once, too.
Welcome to the Primate cage–you can share my bananas. 
First day of grad school.
I had double majored as an undergrad and was the “superstar” of both departments. It was sometime after lunch when I realized that every student in the department had been the “superstar” in their respective departments and that undergraduate superstar did NOT correlate with graduate superstar. The depth and breadth of knowledge that some of the other students were in possession of was astounding (and more than a little humbling).
First term of college. I thought I was going to be in the sciences, and then Gen Chem and Calculus whipped me very very badly that term-- while others in the class were scoring 106% (extra credit!) I was scoring, like, 34%, or 16%. Very, very humbling.
Goddammit, I’m practically weeping.
Lemme tell you a quick story. I teach a group of inner city black children corny poetry in order to teach them some black history. While trying to come up with a name for our little ‘group’, I decided that I wanted it to mention being ‘black’ and also I wanted it to have a scientific meaning. Well, I had heard the term black body and decided to name my group that…Black Body Poetry. Problem is, I could not for the life of me grasp what the hell it meant. And I really did try to research it to death.
That beautiful description you provided is as close as I shall ever come to understanding it, and for that I thank you.
Now…I just have to figure out a way to make it have anything at all to do with black history.