Like I do almost whenever Daylight Saving Time ends or starts, I have congregated a handful of brief video explanations about why we have Daylight Saving Time. Take a look and see if there is one that can assist you explain Daylight Saving Time to your trainees..
National Geographic has actually two videos titled Daylight Saving Time 101. The first one, released in 2015, is a bit more upbeat than the second one that was published in 2019. Both variations are ingrained below..

The Telegraph has a 90 2nd description of Daylight Saving Time. The video doesnt have any narration so it can be enjoyed without sound.

CGP Greys video description of Daylight Saving Time is still a great one even if it isnt as concise as the videos above.

Daylight Saving Time ends today for a number of my good friends in Europe and it ends next Sunday for those of us in North American states and provinces that observe Daylight Saving Time. As someone who gets up early and resides in a northern state, I welcome the change as Ill see the sun an hour previously. And ideally, my kids will make the most of the “extra” hour of time for sleeping next Saturday night.

TED-Ed has 2 lessons that arent specifically about Daylight Saving Time however are related to the topic. Initially, The History of Keeping Time discusses sundials, hourglasses, and the development of timezones. Second, How Did Trains Standardize Time in the United States? describes the role of railroads in the development of the timezones used in the United States (and most of Canada) today.