Wednesday, August 26, 2020

The End of School Computer Labs?

There has been a lot of talk in recent years about doing away with computer labs in schools. BYOD and one to one computers have been talked about and have been growing movements for a while. I wonder if the current situation will be the final tipping point.

My old school removed the computers from the computer labs. The work involved in constantly sterilizing and cleaning them was becoming too much. So students bring their own devices and now connect to virtual machines via the network. They have access to all the school’s licensed software no matter what device. This worked great when we moved to remote learning in the spring.

Besides the cleaning/sterilizing issue this means a lot of new flexibility. Of course it makes it easier if school has to close and students have to learn from home. But in school it opens more rooms for teaching. And if you have small rooms classes can even be split across rooms with teachers in one room, or even at home, teaching to several rooms with safety distancing.

I computer room can have a more flexible layout, perhaps with easily movable tables for group work, focusing on a lecture, or just plain spreading out.

Will computer labs now totally disappear? We’ll see. A lot depends on a willingness and ability to provide computers for every student. That’s easier in wealthy areas than poor ones. But it just may be the way things have to be.

Saturday, August 15, 2020

Book Review: Humble Pi

Recently, I asked my Facebook friends for recommendations for non-fiction books that would not get me depressed. Several people recommended Humble Pi: When Math Goes Wrong in the Real World so I bought a copy. I’m glad I did.

The book presents some interesting case studies in math done wrong. From people confusing units of measure (pounds and kilograms for example)  to engineers changing one variable in an equation and assuming the answer doesn’t change and many more. As you might expect there are a lot of examples where computers play a role.

There are examples of problems caused by variable type mismatches, binary overflows, and people just misinterpreting the results. You’ll get any number of examples you can use with students. A valuable book to teachers of computer science, physics, and mathematics for sure.

The book is written in an easy to read and often humorous fashion. It’s an enjoyable read even if you are “not a math person.” I bought the Kindle edition but I am wishing I hard bought a hardcopy edition to keep on my bookshelf. I’ll be back looking at this one.

Thursday, August 13, 2020

Are You Ready to Help with CSTA 2021

The call for participation in CSTA 2021 is now out. You can learn about the submission process and look at some possible topic areas on the conference information page here. There are several ways to help out with the conference (see below). You can present or you can become a reviewer. Both are very important roles.

I encourage CS teachers to consider submitting a proposal to present. I have been honored to present at the CSTA conference a number of times over the years and have found it a very rewarding experience. The audience is kind and anxious to learn. This summer, the conference being online, added a new and extra facet which I found surprisingly energizing. I am hoping, as I think most of us are, that next summer we will be meeting in person. Either way, presenting at CSTA is a great way to be part of the community and to help expand knowledge

Chances are that you tried something new this past spring. Or will be trying something new this fall semester. That means you probably have something worthwhile to share. Don’t be shy!

Reviewers are also critical to having a good conference. Reviewers read and evaluate proposals and are essential in the process of picking the best presentations at the conference. Please think about helping out in this way.

  • Apply to present: We're accepting submissions for a one-hour session, three-hour workshop, 20-minute mini-session, 45-minute Birds of a Feather discussion, or a poster session. Visit our website for more information on the process and to submit your application. All submissions are due by Nov. 8.
  • Become a reviewer: We invite you to consider reviewing submissions for CSTA 2020! If you've attended or presented at a prior CSTA conference, have a connection to K–12 computer science, and are available between Nov. 23, and Dec. 17, consider volunteering your time!

Wednesday, August 05, 2020

Learning Python Part 2: Distracted by a Turtle

I cracked a book and found out that Python supports turtle graphics. I love drawing pictures with graphics. I have since I was in university. So today I played around with the Python turtle a bit.

Mostly I played with a few of the usual turtle methods and wrapping drawing code inside loops. I had some fun but didn’t learn a lot. I’m not sure that was the most productive use of my time.

It did suggest that using graphics with Python is potentially a way to make learning Python more interesting. I have Mark Guzdial’s book on Media Computation around here somewhere. I’m going to dig it out and see if it the libraries for it will work in my environment.  I want to do more than draw lines.

Tuesday, August 04, 2020

Programming Projects for Learning or Grading

The purpose of school work is to get good grades. Well, at least that seems to be a common view on the part of students. Most teachers will tell you that the motivation for students to cheat is that they are lazy and still want to get good grades.  The recent posts by Mark Guzdial  (linked to at Changing How We Teach Computer Science) have sparked a lot of comments on his blog and on Twitter which had sparked some thoughts on my part.

I have long believed that projects are a great learning exercise for students. I haver become less enamored with them for grading. Cheating seems to show up all to often. Often it is hard to prove cheating because projects are to short, variable names are too likely to be the same logically, and there are limited ways to solve them. I have seen the most creativity and the least cheating (provable or otherwise) on larger projects where students were all doing something completely different.

A common thread in the comments I have been seeing recently is that students cheat not because they are lazy but because they don’t know how to solve the project on their own. This idea resonates strongly with me.  I see a lot of satisfaction on the faces of students who successfully complete projects. They tend to actually enjoy the process when they have success. 

Over the last several years I have increased the number of other means of assessments including multiple choice questions that include reading and understanding code. Comparing quiz results with project results has been interesting. Some students show close correlations between quiz grades and project results. Other students not so much. While I haven’t conducted a rigorous or scientific study by any means, my observations suggest to me that students are copying the projects of others because they haven’t gotten a strong enough grasp of the material. 

I’m pretty convinced that evaluative instruments that require the reading and understanding of code are better tools for understanding what students actually know than looking at projects. That is not to say that looking at projects is useless. To the contrary, students who work hard against the struggle show what they know and don’t know in their code. A project that doesn’t work correctly give a teacher a lot more information about student understanding than a project that works perfectly.

In my ideal world, I would give each student a different project for every concept I want them to demonstrate knowledge of. That is clearly not possible and certainly doesn’t scale to large classes. I’d love to have a way to watch student progress on a project. What do they try and what do they do when things either work or don’t work. I don’t know of a good tool to that right now or even if it is practical. I guess for now teachers will just have to watch students closer.And use other tools for grading and for determining what students actually know.

Sunday, August 02, 2020

Learning Python: Part 1

Python has been on my radar for years but I haven’t really had the motivation to learn it myself. It’s time though for several reasons. Reason number one is that I need a learning goal to keep stretching my mind and knowledge. I don’t have a bunch of students finding new puzzles to solve so I have to make my own mistakes.

First step was to pick a development tool. I have played with a bunch. IDLE, PyCharm, Processing, and some I forget. I didn’t like any of them. So I am using Visual Studio. I expect many to tell me that was/is a horrible choice but its the devil I know so there is that. Many of the tools feel like steps backwards to me. I’ve gotten spoiled by the Intellisence in Visual Studio among other features. IDLE felt like what I used to learn BASIC-Plus 40+ years ago. Anyway, I want to spend my time learning a language not an IDE.

OF course there are two parts to learning a new programming language. Part one is the basic syntax. Part two is the idiom of the language. The first part is easy. The second not so much.

I’ve started with easy stuff. Declaration of variables, simple math, declaration of functions, and control flow. IF statements and while loops were pretty straight forward. For loops are different and idiom rears its ugly head here first for me.

For loops in Python seem to be what I think of a ForEach loops in other languages. Very powerful and useful. On the other hand, how do I do the equivalent of:

for (i=0; i <= 100; i+=5)
for i =0 to 100 step 5

Or do I need to use a While loop to do this? Go ahead, show off in the comments and help me out.

String manipulation, one of my favorite things to code, is probably next for me.I think that will be ok.  Lists and dictionary come after that. I think I will have to read up on them as they look to be thought of differently than arrays in the languages I am used to using. They also look like fun and powerful to use. So there is that.

Classes after that. Hopefully that moves quickly.

Once I get some basics down I’ll start looking into various libraries and what not. Perhaps go back to try some graphics in Processing. Is there an equivalent to Windows Forms like I use with C# and Visual Basic? Or do I have to go backwards again to do that?

At least I’m having fun. Now to go crack a book.