Hackety Hacking the Computer Science Classroom Workspace

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Overview

Our goal is to create at least twelve high-quality problems and solutions that may be used to teach and learn programming.

Note about solution platforms

Initially, we planned to focus exclusively on Hackety Hack. However, now that I have seen your wide range of experience, I think you should feel free to experiment with different platforms, depending on the problem. For example, a particular problem might be better solved with Python rather than Hackety Hack.

Learning to use the appropriate tool is a part of learning to program. To help your audience, please explain why you chose a particular platform with your solution code.

Later on, we might collect multiple solutions for each problem. For example, imagine solving the same problem in Java, Python, and Squeak.

The only limit is that the tools you use should be freely available and cross-platform compatible. This is because we want to be sure that students and teachers can actually use the solutions we provide. Hackety Hack, Python (with Pygame), Squeak, Processing, and Java are all great choices.

What is a problem?

A problem is a learning opportunity. Students should feel challenged to create a solution that can be implemented in the world outside of the classroom. Great problems can be inspired by real challenges that have faced professionals, or academics in the past.

High-quality problems are not exercises. In other words, problems challenge students to implement content knowledge towards a bigger goal. This is the crucial difference between problem-based learning and a traditional model based on testing.

Problem Statement

Your Problem Statement is a short piece of writing (one or two paragraphs) describing a challenge. It should include all of the information the reader will need to solve the problem.

A strong problem statement is like an unfinished story to be completed by the reader.

Sample Output

Provide an example of how the program will look to its user.

Curriculum Connections

Provide a list of content goals to help teachers locate your problem. Some of these content goals will be Computer Science related (e.g. "Understanding if-else logic") while others might be from other fields.

Solution

Provide at least one solution to the problem in running code. It's important that this solution is well-documented with in-line comments.

Where do I get ideas for my problems?

You might think about using existing learning materials as inspiration. For example, look at each chapter of How to Think Like a Computer Scientist: Learning with Python. Why do we learn about these topics? What types of problems do strings help you solve? What problems do arrays solve?

Sample Problem

Problem Statement

Your DJ friend has an enormous collection of vinyl records. She knows the Beats per minute (BPM) of all the records at 45rpm but wants to know how these BPMs will change if she plays the records at 33rpm. She's figured out that the proportion of 45/33 is important but isn't sure how this will affect the BPMs. Can you write a program for this DJ so that she can easily figure out what the BPMs of her 45rpm records will be when she plays them at 33rpm?

Sample Output

Please enter the BPM at 45rpm and press ENTER: 120
The BPM for this record at 33rpm will be approximately 88.0bpm.

Curriculum Connections

To solve this problem, students will:

  • Take input from a user
  • Store input in a variable
  • Perform floating-point division
  • Output data to the user
  • Demonstrate an understanding of proportions

Solution

# First, we ask the user for the bpm of the record on its normal speed
# and store this answer into a variable called bpm
bpm = input("Please enter the BPM at 45rpm and press ENTER: ")

# Next, we convert this bpm to the slower speed and store this answer in 
# a variable called slowbpm
slowbpm = bpm * (33.0 / 45.0)

# Finally, we print a friendly message to the user with the answer.
print("The BPM for this record at 33rpm will be approximately ", slowbpm, "bpm.")

Problems we're working on

Make links to incomplete problems here. Prefix your page names with Hackety_Hacking_Problem_ so that we can find them easily.

Completed Problems

When a problem is complete, move it to this area.