21-Day Data Challenge FAQ

Hello data enthusiasts!

Welcome to the 21-Day Data Challenge forum. Here, you’ll find what the community is saying about the challenge, as well it’s a place to ask and answer questions from your fellow 21DDCers.

Here’s some FAQ about the challenge and the forum:

1. When does the daily challenge launch?
Every day from February 17th to March 9th, the daily challenge will be posted at midnight eastern standard time. Please take time zones into consideration! If you’re on the west coast of Canada, the challenges will be posted at 9pm your time the day before. If you’re in London, England, the challenge will be posted at 5am your time.

2. Why is the challenge not loading in the notebook?
Sometimes the challenge will take a few moments to launch, depending on a number of factors. To try and speed up load time, try checking your wifi and turning off browser extensions, such as Adblock or Privacy Badger. If all else fails, take some time and check back in later.

3. Does the 21DDC work with my browser?
Yes. The 21DDC will work in all major browser programs, including Chrome, Firefox, and Safari.

4. I accidentally closed the window before submitting my answer! Is my work still saved?
If you reopen the browser window within 10 minutes or so, your work should still be cached. Beyond that, you’ll have to rewrite it. Be careful!

5. Can I revisit the challenges after the 21DDC is over?
After March 9th, the challenges will still remain up for an indeterminate period of time. To be safe, save your code onto your computer if you want to preserve it for later reference.

6. Why can’t I win prizes?
For legal reasons, prizes are only available to Canadian residents who are the age of majority in their province or territory. But no matter where you are in the world, you can still learn data science from the challenges!

7. Why can’t I access the challenge?
Click on the “under construction” icon on the /challenges landing page for your current challenge. You can only move ahead to the latest day’s challenge, so wait until midnight ET for the next challenge to open.

8. Why doesn’t the notebook load?
Make sure you aren’t running a VPN/Proxy as users have mentioned it affecting the iframe of the notebook. Browser/OS may affect the load time as well. Message us if you continue to experience issues.

Good luck!
Tim at Lighthouse Labs


I have a public team and someone joined, but I’m not sure who that person is. They haven’t completed any challenges and I want to be able to reach out to them to get them to participate. Is there any way to get the email they signed up with?

Hi All~

I have a general question, and I hope this is the right place to post it.
It is about text data cleaning and analysis. Does anyone have experiences working with Python? Any tip/suggestion/resource/lesson/… that can be shared?

Thank you all in advance :handshake:

Any way to add this to LinkedIn?