I am helping a young friend of mine with her 4-H fair project on Monday. I looked at the guidelines and got an idea of what she needs to do. What I am confused about is if she can only use buttercream frosting.
I think it would be fun to teach her how to do some figure piping with royal icing, but I don't know if it is against the rules.
When I was in 4-H I used fondant on a cake and had no problem, so I would think royal would be ok too. At least at my fair, I think they're more concerned about the cake itself like the shape and size. or the number of tiers.
I judge the 4_H entries at our county fair as well as doing several workshops with the kids each year. In our area, they can and DO learn all kinds of frostings, techniques, designs...you name it! Usually it depends on what the leader is comfortable in presenting, or having outside teachers do special presentations. The last couple of years I have done workshops on fondant/gumpaste and always bring some of my cake toys for them to try as well as telling them how to make things out of things commonly found at home .....less expensive for the families and the parents always appreciate that!
If you are concerned about specifics, see if you can contact the 4-H leader and get clarification. I know our fair book sets guidelines but can be vague on some things!
I downloaded a 4-H cake decorating manual the other day out of curiosity, and they use pretty much everything...they even used something I'd never seen before, an Australian lace nail, and they were using royal icing with it.
I can't remember exactly where I got it because I downloaded a lot of stuff that day...but if you think it would be helpful to you, I'll upload it to a file host and give you the link.