Watchly Safety Review

Stealing Baseball Signs with a Phone (Machine Learning)

Mark Rober
13:30 · 29.6M views · June 30, 2019
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Minor FlagsReviewed June 2026
4Minor Flags
1No Issues

This educational video uses baseball sign-stealing as an engaging way to teach machine learning and coding concepts. While the content is genuinely educational and age-appropriate, parents should note the video demonstrates using technology to gain competitive advantages in youth sports, which could raise questions about fairness and sportsmanship.

Content Breakdown · 5 Categories

Strong & Crude LanguageA little

Contains one mild exclamation ('fricking') which is a euphemistic substitute for profanity. The word 'suck' appears twice in non-vulgar context ('I always sucked at baseball', 'kids drool'). Overall minimal crude language.

See evidence (3)
It fricking works. It works.Early in video during app demonstration
I always sucked at baseball... until now... ok, I still probably suck.Opening statement
adults rule and kids droolDuring wiffle ball game conclusion
Bullying, Cruelty & DiscriminationA little

Contains mild competitive trash-talk between adults and children in a wiffle ball game context. The phrase 'adults rule and kids drool' and the setup of 'proving' adults are better could be seen as mildly dismissive of children, though presented in playful competitive context. The ethical concern about 'using our app against a bunch of little kids' is acknowledged but then dismissed when kids trash-talk first.

See evidence (3)
We want a pitcher not a belly itcher. - And no one says that about my pitcher, so at that point, the gloves came off.During wiffle ball game sequence
we were able to officially prove adults rule and kids droolConclusion of wiffle ball game
And I wasn't sure on the ethics of using our app against a bunch of little kids, but they were scoring runs and stealing bases with impunity and then they got so confident, they started talking trash.Mid-game commentary
Hidden Advertising & Sponsored ContentNot present

Video promotes another YouTube channel (Jabril's) and includes multiple music credits from Epidemic Sound and other sources. The promotion of Jabril's channel appears organic as he's a collaborator on the project. No undisclosed commercial relationships detected, though the line between collaboration and promotion is somewhat blurred.

See evidence (2)
Go subscribe to Jabril's channel!!! https://www.youtube.com/channel/UCQALLeQPoZdZC4JNUboVEUgVideo description and early content
He has an amazing YouTube channel you should check outDuring Jabril introduction
Toxic Behavior ModelingA little

The video demonstrates and encourages sign-stealing in baseball using technology, which while acknowledged as potentially against league rules, is presented as clever and entertaining. The creator explicitly states 'if there are specific rules against using technology to steal signs in your league I am not telling you to break them' but the entire video glorifies circumventing the spirit of fair play. The covert filming techniques (GoPro in cup, 'secretive recon work') model deceptive behavior. The ethical concerns are raised but quickly dismissed in favor of competitive advantage.

See evidence (4)
If you put a GoPro in a cup, you can actually just watch the footage and frame the shot real time and it just looks like your checking dank memes with a drink in your hand. I've actually used this trick a few timesDuring explanation of covert filming techniques
So I asked my buddy Destin to do some secretive recon work.When introducing Destin's footage gathering
And I wasn't sure on the ethics of using our app against a bunch of little kids, but they were scoring runs and stealing bases with impunity and then they got so confident, they started talking trash. - And no one says that about my pitcher, so at that point, the gloves came off.Justification for using app against children
if there are specific rules against using technology to steal signs in your league I am not telling you to break them. Otherwise, from personal experience, you might risk getting some very important people mad at you.Final disclaimer
Engagement Baiting & Manipulative CTAsA little

Contains a direct call-to-action to subscribe to another channel, though not particularly manipulative in nature. The CTA is straightforward rather than guilt-tripping or using exclusion language.

See evidence (1)
Go subscribe to Jabril's channel!!!Video description and early content

What Parents Need to Know

This video teaches legitimate computer science concepts through a baseball application, but it involves using technology to decode opponents' signals in youth games. While sign-stealing by observation is legal in baseball, using apps during games may violate league rules. The creator acknowledges this ethical gray area at the end. The educational value is high—explaining machine learning, neural networks, and coding in accessible terms—but parents should discuss the difference between learning technology and using it to gain unfair advantages. There's mild language (one bleeped word) and competitive trash-talking between kids and adults in a wiffle ball game.

Talk to Your Kids About

  1. 1What's the difference between using your brain to figure out patterns versus using technology? When does a smart strategy become unfair?
  2. 2The video teaches real coding concepts—what interested you most about how computers can learn patterns like our brains do?
  3. 3If you created an app that gave you an advantage in a game or sport, would you use it? Why or why not?
  4. 4How do you think the other team would feel if they found out someone was using an app to predict their moves?
Stealing Baseball Signs with a Phone (Machine Learning)
Protected Viewing

What's This Video About?

I always sucked at baseball... until now... ok, I still probably suck. Go subscribe to Jabril's channel!!! https://www.youtube.com/channel/UCQALLeQPoZdZC4JNUboVEUg Simple app (it's actually just a webpage for now): http://jabrils.com/sp/ Complex app using ML: https://github.com/Jabrils/Uncle-Rober-Baseball-Predictor ***Music*** Dansez - Fasion https://www.epidemicsound.com/track/QXxs7iZ3Rn Dive - Lvly https://www.epidemicsound.com/track/4JmHD4z5Bj Dansez - Fasion https://www.epidemicsound.com/track/QXxs7iZ3Rn Kalimba Jam - Blue Wednesday https://soundcloud.com/bluewednesday/ Take Me Out to the Ballgame -Matt Cherne- https://smarturl.it/einsteinbeats Arrow - Andrew Applepie http://andrewapplepie.com/ Cereal Killa - Blue Wednesday https://soundcloud.com/bluewednesday/ Salamanca - Sarah, the Illstrumentalist https://www.epidemicsound.com/track/nAhVeSoknF Q - Blue Wednesday https://soundcloud.com/bluewednesday/ Too Happy to be cool - Notebreak https://soundcloud.com/notebreak/dubstep-too-happy-to-be-cool Summary: I wanted to see if I could make an app that could decode baseball signs. Turns out we could and it was a great opportunity for me to learn more about Machine Learning and neural networks and artificial intelligence from my friend Jabril. MERCH- They are soft- https://teespring.com/stores/markrober PLEASE CONSIDER SUBSCRIBING: http://tinyurl.com/MarkRober-Sub ****************************************­ I make videos like this once a month all year long while supplies last: CHECK OUT MY CHANNEL: http://tinyurl.com/MarkRober-YouTube FACEBOOK: https://www.facebook.com/MarkRoberYouTube TWITTER: https://twitter.com/#!/MarkRober INSTAGRAM: https://www.instagram.com/markrober/

Frequently Asked Questions

Is this video actually teaching my child how to cheat at baseball?

The video teaches legitimate machine learning and coding concepts using baseball as the example. While it demonstrates decoding signs, the creator acknowledges potential rule violations and doesn't encourage breaking league policies. The educational content about computer science is the primary focus.

What will my child learn from watching this video?

Kids will learn foundational concepts about machine learning, neural networks, pattern recognition, and how computers can be trained to identify complex patterns. The explanations are accessible and use real-world examples that make abstract computer science concepts understandable for beginners.

Is the language appropriate for kids?

The video contains one bleeped profanity and some competitive trash-talking during a wiffle ball game (kids chanting "we want a pitcher not a belly itcher"). Overall, the language is mild and typical of sports settings, but parents of younger children should be aware.

Does this encourage unsportsmanlike behavior?

The video exists in a gray area—sign-stealing by observation is legal in baseball, but using technology may not be. The creator does mention checking league rules at the end. Parents should use this as a discussion opportunity about fair play, rules, and ethical use of technology in competition.

Is this too technical for my child to understand?

The creator breaks down complex computer science concepts into simple, visual explanations (like the "Timmy and toys" example). Kids interested in technology, sports, or problem-solving will likely find it engaging, even if they don't grasp every technical detail. It's designed to spark interest in coding rather than require prior knowledge.

Should I be concerned about the "toxic behavior" score?

The score likely reflects the competitive nature of using technology for advantage and the adults-versus-kids trash-talking during the game. The behavior shown is playful competition rather than genuinely toxic, but it does model using superior knowledge/technology to win, which parents may want to discuss.

What age is "Stealing Baseball Signs with a Phone (Machine Learning)" appropriate for?

Watchly's safety review recommends "Stealing Baseball Signs with a Phone (Machine Learning)" for ages 10 and up. See the content breakdown above for the category-by-category findings behind this recommendation.

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