Getting Others Started

I have been trying unsuccessfully the past few weeks to get my two cousins to try wakeboarding. They are both 10 and like to watch me, I got one of them to say he would try so I did a couple runs so he could see how to get up, on my last run I took a hard fall that once he saw changed his mind, any idea how to get them to at least try to wakeboard? I have no problem with them not liking it after they try but I really think they would like it since they like watching me and like getting tossed around on the tube. I thought they would be wanting to try as soon as I asked them but I think they are scared to try. So any ideas on getting them to try?