A bit more
I would just like to tack on a few things to what snowolf said (which was excellent by the way) and yes FUN is the only important thing here (well after safety)
1: be prepared for a very short day, and thats ok!
2: Keep in mind maslows mountain, it basically says that if the base needs are not met, we will not learn. so too cold, hungry, scared... etc fix that before anything else
3: one thing some kids like, and you will now better than me for your kid, is falling, they find it hilarious. Where i teach we have a surface conveyor that takes you up a very mellow hill, and some of our youngest kids LOVE falling into the fresh snow on the side of the groom. How does this help you? Start them in the middle, then you lead by turning into the fresh snow and falling and laughing, if they follow, they are learning to turn, and laughing!