I tried showing this [old tech][1] programme but they failed to relate to it and got bored really quickly. I think it destroyed my street cred more than anything. 

They did enjoy a clip that showed one of the first home pcs and some games consoles. I found a youtube video showing a [zx spectrum loading ][2] a game. Some jaws dropped and after they begged me to turn off the noise, I let them play some retro games that I found on google

A classroom display may work well. They can then look and read about it in their own time. In the iMac suite I have a poster showing Macs through the ages. It kept them amused for weeks and they appreciated what they have.

  [1]: https://youtu.be/6UfOIfuYJT8
  [2]: https://youtu.be/MtBoRp_cSxQ