5 ms·

I see your point, but I don't know that I feel you've done a good enough job defending it. (I say this as very much not an expert, but as someone who is merely

I see your point, but I don't know that I feel you've done a good enough job defending it. (I say this as very much not an expert, but as someone who is merely very interested in the intersection of CS and education.) Racket was primarily designed for teaching and has been somewhat successful in that regard. I don't know of an empirical study, but if you attend a RacketCon or go to a Racket Summer School you will meet educators who talk about how Racket has positively affected their experience in education. But maybe part of the issue is using Racket for what it's meant to be used for. Racket is good for teaching computer science, which I'm contrasting with software engineering (often just called programming, although I don't like that). It seems like most CS programs at universities are really SWE programs in disguise. Of course, this is often what the students really want: a program to help them get jobs in industry. Racket is good for building a slightly more mathematical framework of programming than a language like Python. The functional nature of the language promotes thinking about problems in terms of data and their relations, instead of in terms of procedures and state manipulation which tends to be how imperative languages are learned. (This is not to say that imperative languages can't be used well, or can't be used in a "mathematical" way, but this tends in general not to be the case.) If the end-goal is to teach students how to approach programming mathematically, then they are more likely to learn better with Racket than Python. You will also have a problem now with students who have some prior CS knowledge disliking Racket because it doesn't aligned with their not-yet-fully-built notions of how programming languages work. The larger your classes, the more influence this factor will have. I think your survey ("Students do not like Racket") would be better if it were correlated with information like this. My gut feeling is that students with zero prior programming experience are likely to have a less extreme negative feeling of Racket than those who had previously learned a little Python, C, Java, Javascript, etc. The issue of students not using Racket later in their degree is certainly problematic. Matthew Flatt (one of the principle authors of Racket) taught Utah's intro course in Racket just twice. When I asked him why it didn't continue, he more or less indicated that he had a hard time with it because it caused problems for students with the rest of the degree program. They learned stuff fine in his class, but the subsequent semester relied on knowledge of Java, and this was no good. Schools where Racket does well are schools where the various curricula are more cohesive in this regard, such as Northeastern and Indiana. (Speaking of which, Indiana should go on your list. I'm pretty sure their intro course is taught in Racket.) You also claim that the Racket group have not published very much data, but you also are lacking the same data. For example, you say: > Despite being ten years old, there is relatively little research to demonstrate the value of “Design Recipes” as a pedagogical approach, especially one that has long term benefits. One research study by the group indicates that students may be more prepared to apply principles of Functional Decomposition through this approach than students who do not, based on studies of the Rainfall Problem. Is this unique to using Racket? It’s a reasonable hypothesis, but not a proven fact. but you don't provide evidence that it isn't the case, nor that Python is a better language for the same problem. I do believe there's value in expressing opinions without facts (or else I wouldn't be here!), but I think in this case your position would be significantly strengthened by having actual data to back up your claims. I'd suggest that maybe your issue with teaching Racket was multi-fold: (a) your students wanted industry-relevant languages (SWE vs CS) and Racket is not that (which indicates either a need for industry-relevant languages or else an explicit explanation of why Racket is a good introductory language); (b) you lacked support from other faculty so students could continue to learn in the Racket environment past their first semester; (c) you don't appear to be a proponent of the whole "Design Recipe" thing, which is kind of essential to the intended Racket teaching methodology. I also wonder about other factors, such as whether your TAs were good at helping with Racket. I want to make clear that I don't think you're wrong by necessity. It's entirely possible that Racket is actually bad for teaching computer science. But it's my opinion (as somebody who learned imperative languages first, Racket later) that your article does not really satisfy your claim, and I find that a little disappointing. As an aside, I might suggest looking more specifically at what Shriram Krishanmurthi is up to. He's the most education-focused of the original Racket group, leading initiatives like Bootstrap to great success. He's also pretty active on Twitter, so if you're feeling up to it you might post your article there and tag him in. ;) (I think he's also on HN but I've forgotten his handle.)

acbart 7y ago
First, let me say I appreciate your lengthy response and your relative neutrality on this. Sometimes, when encountering folks who disagree with my opinions on this, things get a little heated. Case in point - I am very aware of what the person you mentioned says, which is difficult because I have blocked him on social media after our interactions. I originally had a paragraph about how I believe the PL/Racket community can be too rude to interact with. This is a difficult thing to say, but I'm afraid to let it not be said. The way that they communicate their arguments and ideas is frequently inconsiderate. You can say that feelings have no place in academia, but I've seen the impact that this has on potential practitioner adopters, on grad students, on many folks. I hear and appreciate what you are saying about evidence. First, I'll give the usual disclaimer that evidence is hard to come by in CS Education because it's hard to collect properly. Second, I'll point out that I have been involved way more heavily in a completely different sub-branch of CS Education; if you would like to hear evidence for, say, the value of data science as an introductory computing context for non-majors (CS0), then I am very happy to share what I know that is backed up by evidence. Only recently have I started getting involved in actual CS1 research in a deep way - so I can't really take much responsibility for the lack of research. I mean, I've only been a professor for two years now :) I don't know if you were hoping that I'd be able to find evidence in other papers or generate the evidence myself. For the former, know that I tried hard to do a proper lit review on this (and I'm not even going to get a publication out of it!). I even asked some Racket people: one basically repeated Matthias Fellisen's disgusting opinion that CS Ed research is not possible, and the other just pointed to one of their papers citing theoretical arguments. At some point, I'm hoping to ask Kathi Fisler if she has a better set of citations, assuming she'll still talk to me if she finds this document :) As for whether I should be responsible for conducting research to disprove HtDP, I have considered it. I might even do it. Certainly, I am trying to experiment with several methods that can hopefully provide contrasting information. For instance, I want to see if I can replicate the Rainfall success by teaching more explicit functional decomposition and pattern application in my CS1. Of course, I'm also trying to do a ton of other projects, and my job promotion is based on my teaching, not my research. Part of my issue is that I should not be responsible for proving that their ideas work. They thought up a bunch of arguments, and then claimed that This Is the One True Way to Teach. If I made the claim that teaching works better when I punch students at random intervals, and you disagreed, you wouldn't feel that the burden of proof was on your end, right? I should need to prove my Punching Method, to some extent - perhaps at least some pilot studies? The Racket folks made up a lot of claims, and then didn't really prove what they said. That was over 10 years ago! I've been busy getting my doctorate, what is their excuse? Separately, you provide some very valid hypotheses for why my students didn't resonate with Racket. In general, I think you have some good points about SWE vs. CS, but I have a different perspective. There's some mental model here, common in certain communities, that learning happens in a very direct way - if you just arrange concepts in the right way, things will click. I think that learning is a lot more messy and chaotic and driven by a lot of human issues and tough to work with. Transfer is hard. You can't teach CS divorced from programming and this messiness, it's just not realistic. Perhaps a small percentage of my students who are destined to be brilliant Theoretical Computer Scientists and professors will find all the learning to be orderly. But CS is a broad umbrella nowadays, and motivations are complex. I'm not really doing my points justice here, but read some of what Andy Ko and Mark Guzdial have been writing about - I think they're more my kind of CS Education folks :) Finally, I feel like I should at least address your hypotheses: (a) Yes, my students want industry-relevant languages. They all said this to me explicitly, once or twice during class :) I really tried my damndest to give them a good justification for why Racket is a good intro language. I really tried to sell it. I failed - either the arguments weren't delivered well, or they weren't received well. I will point out that some students told me last spring that they earnestly thought I was in favor of Racket for CS1, so anecdotal evidence that I at least tried! (b) Yes, most other faculty don't know why this is being taught this way, and they don't conform their courses to the vision. Should they? What's wrong with their courses that they need to be "Racketified"? What would fixing my junior-level Algorithms course to be more Rackety? Perhaps the Racket folks should offer some explanations. Or, here's an alternative - the PbD curriculum is not solving general purpose problems, and the approaches they teach are not generalizable to other parts of the curriculum. All CS1 courses are full of useful lies - the PbD curriculum's shouldn't be propogated downstream, they should just be tossed out in favor of lies that at least align with the next courses'. (c) I taught the Design Recipe and pretended it was effective. I told my TAs to grade on it, same as the other instructors have done in previous semesters (reusing rubrics helps a lot). Perhaps I'm not a good actor, but I really tried my best to sell it. Maybe my TAs weren't good, but I doubt that. They were all excellent students who excelled at the course when they took it. If they're not good at it, well I don't think we'd have been able to get better ones, so you have to take that as a limitation of the system. I understand why you are disappointed by my article. I am disappointed in the entire HtDP community. I think that this is a bad situation, and I'm not clear that I can make it better by writing an article. However, my goal wasn't to persuade you that Python was better than Racket for CS1. It's to make the points that right now, in my context, I should be teaching Python instead of Racket. Also that the HtDP community should be ashamed of the awful job they've done proving their points, and they should stop being so mean to everyone.

acbart 7y ago

First, let me say I appreciate your lengthy response and your relative neutrality on this. Sometimes, when encountering folks who disagree with my opinions on this, things get a little heated. Case in point - I am very aware of what the person you mentioned says, which is difficult because I have blocked him on social media after our interactions. I originally had a paragraph about how I believe the PL/Racket community can be too rude to interact with. This is a difficult thing to say, but I'm afraid to let it not be said. The way that they communicate their arguments and ideas is frequently inconsiderate. You can say that feelings have no place in academia, but I've seen the impact that this has on potential practitioner adopters, on grad students, on many folks. I hear and appreciate what you are saying about evidence. First, I'll give the usual disclaimer that evidence is hard to come by in CS Education because it's hard to collect properly. Second, I'll point out that I have been involved way more heavily in a completely different sub-branch of CS Education; if you would like to hear evidence for, say, the value of data science as an introductory computing context for non-majors (CS0), then I am very happy to share what I know that is backed up by evidence. Only recently have I started getting involved in actual CS1 research in a deep way - so I can't really take much responsibility for the lack of research. I mean, I've only been a professor for two years now :) I don't know if you were hoping that I'd be able to find evidence in other papers or generate the evidence myself. For the former, know that I tried hard to do a proper lit review on this (and I'm not even going to get a publication out of it!). I even asked some Racket people: one basically repeated Matthias Fellisen's disgusting opinion that CS Ed research is not possible, and the other just pointed to one of their papers citing theoretical arguments. At some point, I'm hoping to ask Kathi Fisler if she has a better set of citations, assuming she'll still talk to me if she finds this document :) As for whether I should be responsible for conducting research to disprove HtDP, I have considered it. I might even do it. Certainly, I am trying to experiment with several methods that can hopefully provide contrasting information. For instance, I want to see if I can replicate the Rainfall success by teaching more explicit functional decomposition and pattern application in my CS1. Of course, I'm also trying to do a ton of other projects, and my job promotion is based on my teaching, not my research. Part of my issue is that I should not be responsible for proving that their ideas work. They thought up a bunch of arguments, and then claimed that This Is the One True Way to Teach. If I made the claim that teaching works better when I punch students at random intervals, and you disagreed, you wouldn't feel that the burden of proof was on your end, right? I should need to prove my Punching Method, to some extent - perhaps at least some pilot studies? The Racket folks made up a lot of claims, and then didn't really prove what they said. That was over 10 years ago! I've been busy getting my doctorate, what is their excuse? Separately, you provide some very valid hypotheses for why my students didn't resonate with Racket. In general, I think you have some good points about SWE vs. CS, but I have a different perspective. There's some mental model here, common in certain communities, that learning happens in a very direct way - if you just arrange concepts in the right way, things will click. I think that learning is a lot more messy and chaotic and driven by a lot of human issues and tough to work with. Transfer is hard. You can't teach CS divorced from programming and this messiness, it's just not realistic. Perhaps a small percentage of my students who are destined to be brilliant Theoretical Computer Scientists and professors will find all the learning to be orderly. But CS is a broad umbrella nowadays, and motivations are complex. I'm not really doing my points justice here, but read some of what Andy Ko and Mark Guzdial have been writing about - I think they're more my kind of CS Education folks :) Finally, I feel like I should at least address your hypotheses: (a) Yes, my students want industry-relevant languages. They all said this to me explicitly, once or twice during class :) I really tried my damndest to give them a good justification for why Racket is a good intro language. I really tried to sell it. I failed - either the arguments weren't delivered well, or they weren't received well. I will point out that some students told me last spring that they earnestly thought I was in favor of Racket for CS1, so anecdotal evidence that I at least tried! (b) Yes, most other faculty don't know why this is being taught this way, and they don't conform their courses to the vision. Should they? What's wrong with their courses that they need to be "Racketified"? What would fixing my junior-level Algorithms course to be more Rackety? Perhaps the Racket folks should offer some explanations. Or, here's an alternative - the PbD curriculum is not solving general purpose problems, and the approaches they teach are not generalizable to other parts of the curriculum. All CS1 courses are full of useful lies - the PbD curriculum's shouldn't be propogated downstream, they should just be tossed out in favor of lies that at least align with the next courses'. (c) I taught the Design Recipe and pretended it was effective. I told my TAs to grade on it, same as the other instructors have done in previous semesters (reusing rubrics helps a lot). Perhaps I'm not a good actor, but I really tried my best to sell it. Maybe my TAs weren't good, but I doubt that. They were all excellent students who excelled at the course when they took it. If they're not good at it, well I don't think we'd have been able to get better ones, so you have to take that as a limitation of the system. I understand why you are disappointed by my article. I am disappointed in the entire HtDP community. I think that this is a bad situation, and I'm not clear that I can make it better by writing an article. However, my goal wasn't to persuade you that Python was better than Racket for CS1. It's to make the points that right now, in my context, I should be teaching Python instead of Racket. Also that the HtDP community should be ashamed of the awful job they've done proving their points, and they should stop being so mean to everyone.