How many different intro CS courses should we have? A question that resurfaces periodically. This time due to an article in which C++ creator Bjarne Stroustrup posits that different audiences would benefit from a different intro treatment for CS. Perennial CS Blogger and friend Alfred Thompson shared his thoughts on the subject here.

The thought is that someone who's going into academic CS needs one thing, a software engineer another, a non CS person who could benefit from some programming within their field something else.

A person looking towards a PhD in CS might need more theory than say a Software Engineer, although, I agree with Alfred in that Software Engineers benefit from more in terms of data structures and algorithms than say what a coding bootcamp provides.

On the other side, a non CS major could benefit from a more end user programming course that leans heavily on libraries along with a data analysis or statistical bent.

Seems to make sense.

Stroustrup was talking about college offerings but Alfred, in his post brings it to the high school level and notes that while a college may or may not have the resources to offer multiple intro CS classes, high schools likely won't. He also talks about how APCS Principles could or maybe even should be the single intro course.

I agree with Alfred - high school's don't have the resources to offer multiple pathways and I'll go further and say that in High School, I think a single intro course, which should be required is preferable so long as its well designed and well taught.

In college a student might already know their desired path so should be able to chose a CS class that matches that path. There should also be a more general CS0 for kids who haven't decided yet.

High School isn't about picking a major, it's about, among other things, creating a well educated populace. As such, students should be introduced to a variety of fields and CS should be one of them. Now, some readers will be adamantly against this and say that CS shouldn't be required. Well, as long as they think math, biology, history, English and the rest shouldn't be required then I guess that's a fair position. Otherwise, why is CS a less important field?

Now, of course, the quality of the course becomes important. It shouldn't be a deep dive programming course that only a computer scientist would love, that is APCS-A or similar. It should have a programming component and should introduce students into various CS fields and how a computer scientist thinks. It should also show how CS interacts and is useful in other subject areas and how CS and technology are important in society. All that good stuff.

Can this be done? Sure - Stuy's one semester intro course does a pretty good job at it and their full year version does an excellent one.

I don't think, however, that APCS Principles should be the answer. It likely will be the answer because it has the College Board and all the other big players behind it and as the saying goes "nobody ever got fired for hiring IBM" but it shouldn't be.

The course, whatever it is also has to be taught by a very knowledgeable teacher and frequently this isn't the case.

Now, why don't I think it should be APCS Principles, let me tell you what I've observed over the past decade.

What I've observed can be attributed to the course, the teacher, or maybe both.

I ran an honors CS program at Hunter College and every year I admitted a new cohort. From my third year on I accepted about 50 kids per cohort. For each incoming class, I placed them based on their APCS experience. If a kid took APCS-A, regardless of class grade or AP score, I placed them in to my CS1 class - similar material but in C++ and they all did great. The rest went in to my CS0. The majority of the kids who went to CS0 had taken APCS Principles in high school and almost all had gotten a 5 on the exam.

The truth of the matter is that the majority of my students who took and passed APCS-P would have been better off with nothing. A small number each year were decently prepared, either from their APCS-P class or elsewhere - they had some fundamental programming experience, understood some of the "big issues" and had some general exposure to CS. The majority of those kids who had APCS-P, however didn't and in some cases had acquired bad habits and faulty knowledge.

Was this the fault of the course or the teacher? Maybe a little of both. I actually don't want to blame the teacher per se here - they're frequently placed in a rough situation - they don't know the subject and are trying to do right by their students, but their preparation - PD from the NYC DOE, Code.org, and others has been woefully insufficient.

Now, a well prepared, knowledgeable CS teacher can turn APCS-P into a good course - that was evident when I saw the few well prepared kids - each year coming from the same schools with the same teachers. The Stuy intro course could in fact be easily adapted to be a superset of APCS-P. On the other hand, APCS-P can be a wasted year in spite of a kid "earning" a 5.

So what are we left with? While we've come a long way in terms of CS offerings there's still a long way to go. We're currently not doing a good job across our states to find and prepare the number of qualified CS teachers that we need. We're doing a better job with offerings but offerings without great teachers isn't the answer.

We need to keep pushing on promoting the good rigorous teacher preparation programs out there and call out the ones that are fluff. We've got to keep pushing for a required CS class in the high school. It should be a single general course for everyone but, finally getting back to the original issue, it should prepare students so that they can take a follow up CS class appropriate to their interests when in college.