Modifying a Chromecast to play Youtube

I am a member of a student group at my university that helps local non-profits and the like with engineering projects. One of the organizations wants a Youtube player that someone with a developmental disability could use. They want to be able to plug something into a monitor and control it with a set of large buttons. When powered on, it would go straight to Youtube and start playing videos from a certain channel.

My question is: Is there a way to modify the Chromecast to make it do something like this? It seems like a Chromecast would be capable if it could be programmed to access a certain website and somehow linked up with external hardware. Would this be at feasible?

My understanding is, the Chromecast has very little software on it. The playback controls you are talking about are on a 3rd party device such as an iPhone, Android phone, Tablet, or PC running Google's Chromecast software or 3rd party software which has been written to support the Chromecast SDK. The Chromecast device itself just fetches and plays the video data it's told to play.

Here's the documentation for the Chromecast SDK if you want to create your own software to talk to a Chromecast device:
https://developers.google.com/cast/docs/developers