9 Top Platforms to Practice Key Data Science Skills

Which platforms would I recommend as a go-to for learning and practicing data science skills? The list would change every day, depending on my mood. Here’s today’s list with an overview of each platform.

9 Top Platforms to Practice Key Data Science Skills


The nice thing about existing online nowadays is that learning is no longer gatekept. You can read, practice, quiz, and program all by yourself, from the comfort of your own home, without paying for a degree.

And because data science is seen as a tricky skill to learn, many employers aren’t worried about where you learned to code in Python or any other data science skill, just as long as you can do it.

In this article, I’ll break down nine data science learning platforms that provide you with an interactive learning experience. These come with a variety of resources, including video tutorials, interactive coding exercises, and quizzes, to help you build and solidify your programming and database management skills.

Let’s dive in. In each section, I’ll explain what the platform is, what you can learn, how much it costs, and what sets it apart from the other eight platforms I’ll touch on.

Here’s an overview of each platform for quick reference.


9 Top Platforms to Practice Python, SQL, and Coding


1. Codecademy


Codecademy is a platform designed specifically for learning how to code.


What Is This?


Codecademy is an online learning platform that offers courses and tutorials on programming, data science, and web development. It’s a super popular choice among beginners and those looking to improve their coding skills.


What Can You Learn?


With Codecademy, you can learn a ton of different programming languages such as Python, JavaScript, Ruby, HTML, CSS, and more. No matter what your flavor, you’ll find a course for it. Codecademy also offers courses on data science topics like SQL and data visualization, as well as web dev tools such as React and Git.

I personally love Codecademy because it’s so interactive. The platform gives you lessons and coding exercises that help you build real-world projects and understand the fundamental concepts of programming.


How Much Does It Cost?


On their website, their logo is literally “learn to code for free.” There IS a free level, where you can get courses like “Learn SQL” and “Learn Java: Introduction” for free.

However, if you want to further your knowledge and access more advanced courses, you’ll have to pay $34.99 a month, or $17.49/month if you pay annually.


Key Benefit?


Codecademy stands out because of its ease of use. It’s ultra-beginner-friendly. Many coding platforms call themselves beginner-friendly because that’s their target demographic, but Codecademy is perfect for someone who’s never typed a line of code in their lives.

There are tons of free courses you can try out to get a sense of that language, and their teaching style works for you.


2. Coursera


9 Top Platforms to Practice Python, SQL, and Coding
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Coursera is a platform for universities and companies to upload video courses. Among other topics, they have a whole host of popular data science instructors.


What Is This?


Coursera is the destination for online learning run by universities. They do online courses, certificates you can hang on your virtual LinkedIn wall, and even full degree programs. They partner with universities like U of Michigan, Yale, Rice, Imperial College London, and more.

Courses typically run for between one to nine months.


What Can You Learn?


On Coursera, you can learn pretty much any skill, including courses like “The Science of Well-Being,” “Introduction to Psychology,” and “Financial Markets.”

They also offer:

  • Guided projects. These are more hands-on, shorter little nuggets where you’ll come out with a specific skill.
  • Specializations, which are typically further learning in a skill, such as Northwestern’s “The Art of Sales.”
  • Certificates. These offer you a tangible outcome of being “certified” in whichever skill you pick.
  • Degrees. These are entire degree offers.


How Much Does It Cost?


Some courses are free to access, like the first three courses I listed above. Some guided projects, like “Docker for absolute beginners,” start at $9.99/month to access. If you enroll in a more useful course, like a specialization or a professional certificate, those run at $39.99 a month. Degrees, naturally, cost more - they start at $9,000 a degree.


Key Benefit?


Coursera has a huge variety of courses for a fairly reasonable price, run by top institutions like Yale and IBM.  You can get practical skills, a grounding in a wider topic, or go deep with a specialization.


3. StrataScratch


StrataScratch is an interview question platform.


What Is This?


StrataScratch has 1000+ real interview questions from top data science companies, both coding and non-coding.  It’s geared toward folks who are ready to apply for and get a data science job.


What Can You Learn?


This is a much more practical, outcome-focused platform. Rather than teaching you new skills from scratch, this platform is best if you already have some knowledge and want to test yourself or if you want to practice for an upcoming interview.

On the coding side, you can practice PostgreSQL, Python, MySQL, R, and MS SQL Server questions. For non-coding questions, you can practice system design, probability, business cases, statistics, modeling, technical, and product questions.

You can also filter by difficulty and company.

StrataScratch also offers data projects like Market Analysis in Dublin, and guides, for example, SQL Time and Date Manipulation. These more hands-on projects can be useful if you want to add these to your portfolio.


How Much Does It Cost?


There’s a free tier, which includes some but not all questions, both with and without solutions.

For the $32/month tier, you get access to the full roster of interview questions and solutions.

Finally, there’s a yearly option that costs $139/year (or lifetime for $289) that additionally includes access to the data projects and in-depth solution guides to various coding questions aimed at data scientists with 1-2 years of industry experience.


Key Benefit?


Because these are real questions taken from real data science interviews, you’ll get hands-on experience with exactly what companies are looking for.


4. Boot.dev


Boot.dev is home to courses to help you become a backend developer.


What Is This?


Boot.dev is an interesting platform that aims to patch the gap between college degrees and e-learning platforms. College degrees are slow and expensive. Places like Coursera focus on the front-end. If you want to practice Python, SQL, and other coding skills to get a job as a backend dev, you’ll struggle.

They organize the platform around “tracks,” which include languages, guided projects, and portfolio projects.


What Can You Learn?


You can learn Python, JavaScript, and Go as the premier backend coding languages. But you’ll also be taught more computer science-focused skills and concepts, like algorithms, object-oriented programming, and cryptography.


How Much Does It Cost?


Boot.dev costs either $39/month, $249/year, or $999 for the lifetime price. For all those tiers, you get the same benefits: access to all the content, a job-ready portfolio of coding projects, certificates of completion, and access to the Discord server.


Key Benefit?


There are very few places to get learning geared to help you become a backend developer vs a frontend developer. Maybe because front-end dev is seen as more approachable, most e-learning platforms focus on skills like HTML and CSS.

This is one of the only platforms I’ve seen that champions back-end learner.


5. Udemy


Udemy is an online learning platform with courses that anyone can upload.


What Is This?


Udemy is similar to Coursera, but with one key difference: anyone can upload video courses, not just universities or organizations. Like Coursera, Udemy can give you access to a ton of courses about all sorts of skills, but there is a great selection of data science skills.

This means that Udemy offers a wide range of courses, from beginner to advanced, taught by experts, professionals, and individuals.

Udemy's courses are designed to be accessible and flexible, with video lessons, quizzes, and projects to help students build practical skills. The platform also offers lifetime access to course content, so students can learn at their own pace and revisit the material as needed. Udemy's courses are not accredited, but many of them come with certificates of completion that can be used to showcase skills and knowledge to potential employers.


What Can You Learn?


The better question is, what can’t you learn? But here’s a quick upshot of some of the best courses on offer:

  • Programming and Development: including web development, mobile app development, game development, and more.
  • Data Science and Analytics: including machine learning, data analysis, big data, and more.
  • Business: including entrepreneurship, marketing, sales, and more.
  • Design: including graphic design, web design, interior design, and more.
  • Personal Development: including personal finance, productivity, leadership, and more.
  • IT and Software: including cybersecurity, network and information security, cloud computing, and more.
  • Marketing and Sales: including digital marketing, email marketing, social media marketing, and more.
  • Music, Art, and Photography: including music production, music theory, photography, and more.


How Much Does It Cost?


You have two options:

  • You can buy individual courses like “Learn Python for Data Analysis and Visualization,” which are priced anywhere between $15-$30 for lifetime access to the course
  • You can subscribe to the monthly personal plan starting at $16.58 a month, which gets you access to over 8,000 courses, and 4,000+ practice exercises, taught by 3,000+ top instructors.


Key Benefit?


The massive breadth of Udemy is its strength. You can find a course not just on any language but for any purpose, like “Python for Object-Oriented Programming” or “The Complete Guide to React.”

And because anyone can upload a course, you’re bound to find an instructor you gel with.


6. edX


9 Top Platforms to Practice Python, SQL, and Coding
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edX is kind of like Coursera Ultimate. edX has a partnership with several prestigious universities, including Harvard, MIT, and UC Berkeley.


What is This?


Similar to Coursera, edX offers online courses from top universities and institutions. However, edX specializes a little more, both in terms of who they partner with and the skills on offer. For example, edX offers verified certificates, professional certificates, and micromasters, while Coursera only offers specializations, professional certificates, and degrees.

Coursera is also more self-paced, while edX has deadlines for exams and assignments.


What Can You Learn?


With 3,000+ courses to choose from, you’ll be able to find a good data science skill to learn. This platform offers “Intro to Analytics Modeling,” “Machine Learning with Python,” and “The Essentials of Data Literacy,” just to name a few.


How Much Does It Cost?


It varies from course to course, but edX is a little more expensive than Coursera, as a rule. You can access almost any course for free to audit it, but that comes with limitations – you only get access to the material for a month, you don’t get a certificate, and your assignments aren’t graded.

If you want the verified track, prices run from around $49/course to $149/course.

They also offer bootcamps, which run into thousands of dollars. For example, UC Berkeley’s 24-week coding bootcamp costs $13k.


Key Benefit?


This one is pretty comparable to Coursera. The main benefits are that it’s more guided than Coursera, and you might be able to get some more brand name recognition with their certificates.


7. Kaggle


Let’s take a step away from learning platforms. Kaggle is, instead, a competition platform.


What Is This?


Kaggle’s a very popular, very well-run data science competition platform with a lean towards machine learning specifically. It’s owned by Google, and it has tens of thousands of data sets to practice on.

You’ll get:

  • Competitions, in which participants compete to develop the best solution to a problem using a provided dataset. Competitions are sponsored by organizations looking to solve a specific problem and offer prize money to the winners.
  • Public Datasets: Kaggle provides access to a large number of public datasets, which can be used for practice, research, or competition submissions.
  • Notebooks: Kaggle provides a cloud-based Jupyter notebook environment for data science and machine learning, which allows users to easily write, run, and share code with others.
  • Discussions: Kaggle has a large and active community of data scientists and machine learning practitioners who participate in discussions, ask and answer questions, and collaborate on projects.


What Can You Learn?


On Kaggle, you can learn skills like data analysis, machine learning, programming in Python and R, and data prep.

Check out some of the competitions on offer and see what skills you want to polish. For example, you can participate in the advanced regression techniques challenge, microbusiness density forecasting, or computer vision.


How Much Does It Cost?


It’s all free! Enter competitions, download datasets, and take a short course, all for free. That’s one of the big benefits of Kaggle being owned by Google. It’s well-funded and hence can afford to be free for players/competitors/learners.


Key Benefit?


It’s very helpful to get access to real, crunchy data and real, crunchy problems. Once you’re done with e-learning and you want to push yourself even further, this kind of challenge-based platform is good for refining your skills further.

Plus, having access to and guidance on so many data sets means you’ll be able to craft and add some fun data science projects to your portfolio.

Finally, the competitive angle works for some learners!


8. HackerRank


9 Top Platforms to Practice Python, SQL, and Coding
Image from canva


Let’s look at HackerRank, another website for coding challenges.


What Is This?


HackerRank is a website for coding challenges and competitions for software developers to improve their coding skills.

Many companies use it as a fun way to screen job candidates for software development jobs. The platform offers a wide range of categories to choose from, including algorithms, data structures, mathematics, databases, and more.

As a random person on the internet who might want to learn Python, SQL, and other coding skills, it’s a great place to create a portfolio.


What Can You Learn?


The way HackerRank works is like a combination of a portfolio and Kaggle. There are ranked competitions you can take part in, and you can also get certified in languages like Go, C#, and Java.

They have three areas where you can learn:

  • Prepare. This includes an interview prep kit, some basic certifications, and learning on various topics like algorithms, data structures, and mathematics.
  • Certify. This zone has all the certifications you’d need, from R to SQL to JavaScript.
  • Compete. This is the more Kaggle-esque side, which offers competitions and contests to show off your knowledge and earn prizes or renown.

Basically, it’s a good place for active job seekers – and anyone else who wants to learn – to practice and test their coding skills in a challenging and competitive environment.

HackerRank also gives you resources, tutorials, articles, and sample code.


How Much Does It Cost?


Here’s the fun part: it’s primarily a product for companies to hire people. That means that as a candidate, you actually get the product for free (because, in some senses, you are the product).


Key Benefit?


The unique thing about HackerRank is it’s designed for companies, not individuals. That makes it exceptionally useful for individuals to see what companies need to hire someone. You get the interview’s view of yourself, so you know what skills to focus on.

It’s ideal for someone who wants to get a job in data science.


9. StackOverflow


Let’s take a look at this question-and-answer platform.


What Is This?


It’s a little cheeky of me to include StackOverflow as a learning platform because that’s not really what it’s designed for. But it was one of the best platforms I used to learn Python and R organically. And best of all, it’s free.

StackOverflow is a place for programmers, developers, and software engineers to post questions and get crowd-sourced answers. Answers can be voted up or down depending on their helpfulness and accuracy.

It’s a huge repository of coding questions and answers going back for years.


What Can You Learn?


  • Python programming: Many questions and answers related to its syntax, libraries, and best practices.
  • SQL: Including queries, database design, and optimization techniques.
  • Algorithms and data structures: Sorting, searching, and graph algorithms.
  • Web development: HTML, CSS, JavaScript, and web frameworks such as Django and Ruby on Rails.
  • Debugging: So many questions and answers about debugging techniques and best practices.
  • Software design: Learn about software design patterns, architecture, and best practices.

The best way to learn on StackOverflow is by asking and answering questions. Start basic - look for baby questions in Python or SQL that don’t yet have an answer. You’ll soon get a ton of peer feedback on the quality of your answer so that you can improve from there.

It’s intimidating, but it’s a great way to sharpen not only your actual coding skills but your communication skills too.


How Much Does It Cost?


It’s free! Totally, 100% free to make an account and ask or answer unlimited questions.


Key Benefit?


The best thing about StackOverflow is that it wasn’t designed as a learning platform. These are not carefully designed questions and answers – they are real, crunchy, human-world problems with untidy data. And you’re going to get real peer feedback from real data scientists.

It’s a real challenge, but it’s a superb way to learn.


Final Thoughts


In conclusion, the beauty of the digital age is that education is now at our fingertips. Data science is a hot topic, and many employers don't care where you learned it as long as you can rock it.

This article breaks down nine amazing and somewhat unconventional platforms that make learning this in-demand skill a breeze. With video tutorials, interactive coding exercises, quizzes, and IRL data, you'll be able to sharpen your skills and show the world what you're made of.

Don't wait any longer. Pick a platform (or nine - these are not exclusive!) and start learning data science today.
Nate Rosidi is a data scientist and in product strategy. He's also an adjunct professor teaching analytics, and is the founder of StrataScratch, a platform helping data scientists prepare for their interviews with real interview questions from top companies. Connect with him on Twitter: StrataScratch or LinkedIn.