The undergraduate course experience at a number of colleges and universities across the world includes introductory science classes. Some colleges require only science-based majors (including sciences and engineering) to take the introductory science classes, whereas others require students majoring in all subjects to take at least some introductory science classes. All my examples are drawn from the United States, but the questions that I raise are of general interest, and I'm interesting in hearing about people's thoughts based on their experiences studying or teaching at the undergraduate level, regardless of geographic location.

I want to focus on one particular type of introductory science class: the large introductory science class. I'll identify the three key features of the courses I'm talking about:

  • The class size is large: Classes with more than 75 students would qualify as "large" in my view, whereas classes with fewer than 50 students. The 50-75 range is more ambiguous, and may depend a lot on how the course is run.
  • The class is an introductory general requirement class: I'm thinking of classes that first-year college students (freshmen) are generally prepared to take and would take if they have adequate prior preparation and do not intend to major in the subject. I'm excluding Honors classes here (though Honors classes are anyway rarely that large).
  • The class is a science or math class: I'm including physics, chemistry, biology, mathematics, computer science, geology, and astronomy here.

I'm interested in the following questions:

  • What has been your overall experience with large introductory science classes as a student, a TA, or a professor? My general impression is that evaluations of these classes generally run more negative compared to other classes, but I hardly have access to a representative sample.
  • To what extent did your experience (as a student) with large introductory science classes influence your decision regarding career, major, minor, and future elective classes? For instance, did a bad large intro calc class turn you off math? Did a great intro chem class make you decide to minor in chemistry?
  • Did your large introductory science class make use of modern technological aids such as clickers or online discussion forums? If so, how did these affect your course experience?

PS1: Here are a few links I get by Googling for large introductory science classes, and some of them may be of interest: Large Introductory Computer Science Classes: Strategies for Effective Management, Teaching Large Introductory Survey Courses, and Introductory Biology Courses: A Framework To Support Active Learning in Large Enrollment Introductory Science Courses. There is also some research indicating or suggesting that introductory science classes play an important role in encouraging or discouraging the choice of STEM careers, and "fixing" such classes has been hailed by many people as a way of getting more people into STEM careers and also potentially reducing gender or ethnic disparities in the number of people in such careers.

PS2: Clicker technology has been used in a variety of large classes. The simplest implementation is to use clickers to get answers to simple multiple choice questions (correct response rates varying between 30% and 70% in general). For instance, this chemistry lecture at MIT uses clickers in the standard fashion (here's an equivalent lecture that does not make use of clickers). Eric Mazur of Harvard, a proponent of Interactive Engagement, uses clickers in a more fancy way: he first asks students to attempt the question on their own and convey their answer using a clicker, then he gives people some time to discuss and give their updated answer using a clicker.

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15 comments, sorted by Click to highlight new comments since: Today at 1:46 AM

I sat up front in my large chemistry class and acted like it was a small class.

I had a bad habit of sleeping through a lot of my classes and learning mostly from the textbooks and homework assignments anyway...

I spend an inordinate amount of time thinking about these questions and in grad school the issue of "fixing" lower level STEM courses was one of the primary recurring discussions among my friends.

For my part I am slightly too old and/or my university was slightly too hidebound to adopt clickers before I graduated. The primary mode of instruction in chemistry classes was always passive slide shows which are dreadfully hard to attend to, and on top of that introductory chemistry courses are riddled with lies-to-children and unexplained rules of thumb which interfere with intuitive understanding of chemistry. Physics was standard derivations-and-examples whiteboard lecturing with an extremely painful online homework component. Calculus and differential equations were improved by the inclusion of labs relying on the Maple package.

I will say that in general intro classes were stressful, unpleasant, and demoralizing for me, and I am somebody who went on to get a PhD, so you could safely say that I struggled through despite those courses, rather than being excited by them. I think the reason I think and talk about this so much is that this fact makes me angry. Chemistry, physics, mathematics, electronics, geology - these are beautiful and fun things which I now love, and introductory courses, rather than teaching me to love them, seemed designed to systematically ruin them for me.

So, my chemistry education is actually pretty sad. I haven't finished a formal class since high school (and basically everything I've learned since them comes from my physics education), but the story of the intro chem course I started in undergrad seems relevant to this thread.

Around sophomore or junior year of undergrad, all of my pre-med friends started complaining about organic chemistry, and so I decided to take the chemistry track to see if it was as tough as they said. I had to start with the introductory chemistry class of 300 students. On the first day, the professor did a quiz; what's the base SI unit for length, weight, time, temperature, and amount? Once you wrote down your answers, everyone raised their hand, and then put down their hand if they got a question wrong. Maybe 10% didn't get the meter, maybe 20% of the class failed to get the kilogram (an understandable mistake, if they put 'gram' instead), maybe 10% failed to get the second, around 30% failed to get the Kelvin (another understandable mistake, if they put 'celsius'), and then around 29% failed to get the mole.

I looked around, saw that two hands were still up besides mine, and decided to drop the class.

What has been your overall experience with large introductory science classes as a student

Depends on topic.

If it's humanities, social sciences, or biological sciences, you are wasting your time in large intro classes. Try to write to the professors in higher levels and see if you can't skip the lower levels. The faster you reach high level coursework, the better. You know you've hit high level coursework when your assigned readings are primary literature and your turned-in assignments have primary literature citations. You can make up any missed knowledge on the fly with a simple google search.

If it's chemistry, computer science, or anything quantitative (physics, math, engineering) then you need to sit though the intro course if you aren't totally confident that you know the material, because the next course will be extremely cumulative on the knowledge you gain here.

(I may be biased, since most of my interests have been in biological/social sciences and so I might just have known more about those things starting out).

You know you've hit high level coursework when your assigned readings are primary literature and your turned-in assignments have primary literature citations.

This does not apply to math or physics, where you use textbooks up until you do independent research at the Masters or PhD level.

My interpretation of that sentence was that it was intended to apply only to humanities, social sciences, or biological sciences based on the context of the paragraph it resides in.

What 9eB1 said is how I intended it to be interpreted.

Also, that's a big part of the reason I like biological and social sciences better than chemistry/physics, despite being of a quantitative mindset. I'm impatient to get to the science part.

I graduated a couple of years ago in Engineering. (Israel)

In general, it took more effort with large intro class sizes.

I think the main reason for this is not the size itself but the fact that for a large number of students these classes are not very relevant to their future profession (or so they thought). For example, math for engineering/computer science students. I think the motivation of the class in general is more important to your experience.

Regarding your other questions, the experience did not affect my career decisions and in most of the classes the use of technology was restricted to a class website.

I graduated a couple of years ago in Engineering. (Israel) In general, it took more effort with large intro class sizes. I think the main reason for this is not the size itself but the fact that for a large number of students these classes are not very relevant to their future profession (or so they thought). For example, math for engineering/computer science students. I think the motivation of the class in general is more important to your experience.

Regarding your other questions, the experience did not affect my career decisions and in most of the classes the use of technology was restricted to a class website.

I tested out of most of the introductory general required classes in undergrad. My undergraduate degree is in engineering. My department's introductory classes generally were broken into multiple sections of about 30 students, so my experience here is perhaps not representative. The 4 large (100+ student) classes I took were in the math and physics departments.

In the physics classes (which were specifically for engineers, not physicists), the actual topics were dumbed down so much that I had to modify my thinking to do well in the class. And I found the classes to be dreadfully boring in general because the more interesting topics that used math were avoided. Anything involving more than the simplest calculus was avoided. If I could think of a way to do something involving differential equations, surely that was not what the professor wanted. I often had difficulty figuring out why certain (unnecessary) assumptions were made, and I came to the conclusion that they were made to make the class more manageable for the least capable students. Often which assumption to use was ambiguous because any number of bad assumptions could be made.

My experience here is that these classes were designed for the lowest common denominator, and with a large sample size your probability of having someone who'll really hold back the class is near 1. Often this worked to the detriment of the most capable students. I speculate this was done because the engineering school wants to produce more engineers. Seems that their main approach to this is to dumb down classes. I'm somewhat convinced this does more harm than good, partly because I think most of the least capable students would struggle no matter what they were given, though I don't have strong justification for these beliefs at the moment.

Another impression I got from the physics classes was that the professors didn't want to teach these classes. They seemed to consider it a chore, like taking out the trash. There was no consistency between semesters or years in who taught these classes. I'd guess the physics department required professors to teach these introductory classes on a rotating basis, i.e. "It's your turn to take out the trash." There was no passion in these classes, which contrasted heavily with the one upper-level physics class I took.

This did not change my desire to become an engineer. I would fill in gaps in my knowledge on my own time. These classes mostly harmed my time efficiency.

One of these classes required me to buy a clicker, but it never was used in the class. One of the courses used some online homework thing that I thought was dreadful, mostly because I had a difficult time thinking in the constrained way they wanted me to, and also because some of the answers in there were wrong! These courses used Blackboard to manage the other course content, but I didn't use any of the advanced features. I recall downloading assignments and checking my grades.

The large math classes (calculus and differential equations) were for all majors (including math majors) and I didn't feel the topics were dumbed down or that the professors didn't want to be there. My impression was that the professors were not concerned that people couldn't keep up. If a student couldn't keep up, that was their problem. I think this might have partially motivated me to take more elective math classes than physics classes during undergrad (2 undergrad + 1 grad math class vs. 1 undergrad physics class), but applied math is more my interest, anyway.

The math classes had their own websites. No advanced things like clickers or Blackboard were used.

I found the textbooks for the physics classes to be poor jumping off points for more advanced topics. Once you understood calculus, there was little reason to read these books. They also were basically worth no money after the class was over. I vaguely recall throwing mine away because they were so worthless. In contrast, I still own and sometimes refer to my calculus and differential equations books.

I often had difficulty figuring out why certain (unnecessary) assumptions were made, and I came to the conclusion that they were made to make the class more manageable for the least capable students.

I found this when I TAed physics for engineers, which was sad. The professors (through experience, no doubt) didn't trust students to propagate errors by adding in quadrature, and so they were told to just add the standard deviations together. I was scared by the idea of an engineer who couldn't sum errors that way.

Interesting to hear your experience as a TA validates mine as a student. That's a good example of what I mean by an unnecessary assumption or simplification that was done purely to make the class more manageable for some students.

A not-insignificant portion of engineers don't know much anything about physics or math and want nothing to do with either. This is very scary, because these people tend to blindly follow standard engineering practice (which is not necessarily correct) or worse, make up something that is very wrong. A friend of mine told me they went to a job fair and heard a recruiter for an engineering company brag that you won't have to do any more calculus if you worked for them.

As far as I can tell, a significant fraction of the people in every major don't really understand it, don't care very much, and are continually half-assing everything. The problem with just flunking these guys is that they can still be valuable to employers, and their tuition money is nice to have.

Why are you interested?

I took intro physics and math courses 2 years ago and intro CSE 1 year ago at a large American public school.

The physics classes are easy. I mean, really easy. You don't need instructor interaction or TA help to perfect every test in intro physics courses. It's the same for intro calculus, with the caveat that you need to be good at algebra or quick with a TI-89 to perfect calc. I had a lot of fun in physics, and I had a great professor who effectively used clickers by passing around a sheet with big numbers printed on it. He'd ask us a multiple-choice question and we'd fold/display our answer.

CSE was a little different, since there's homework to be done and it was harder to get a 4.0. This one will vary from school to school more than physics I think.