“Free-choice” learners are people who learn outside of a formal learning environment. The video platform YouTube is a popular place for free-choice learners to educate themselves. The author of this article produced a YouTube channel with fifty-one videos on city planning topics to determine how many free-choice learners could be taught on the platform. Millions of viewers, most with no prior formal educational experience with city planning, watched the videos over a two-and-a-half year pilot study. YouTube can be a powerful tool for education beyond the classroom, but the platform’s recommendation algorithm poses challenges to reaching all demographic groups.

“自由选择”的学习者是在正式学习环境之外学习的人。视频平台YouTube是自由选择的学习者进行自我教育的热门场所。本文的作者制作了一个YouTube频道，其中包含有关城市规划主题的五十一个视频，以确定可以在该平台上教多少自由选择的学习者。数百万的观众在为期两年半的试点研究中观看了这些视频，其中大多数人以前没有进行过城市规划方面的正式教育。YouTube可以成为课堂以外教育的强大工具，但是该平台的推荐算法给覆盖所有受众群体带来了挑战。