We have 2 kids that have been at the lake with us since they were born (1st kid in the boat at 5 days old). I agree with @fu_man, the kids have to have fun, which will make life easier on you and hopefully promote them participating once they are old enough. We started with a thin, comfortable life jacket (non coast guard approved speedo swim vest) that went on when we got to the lake and did not come off until we left (food stains and all, did not let them take it off because they did not want to put it back on). The goal of the vest was simply to keep them above water if they were to fall in and we could grab them out. My husband has done a great job of playing with the kids inbetween sets to keep them happy. Now that they are older (8 and 10), we can all ski a set, then have play time. When we had friends who could drive at the lake, we would take advantage of that , one of us skiing while the other played with the kids to limit the time they had sitting in the boat. Now we have to fight with them to get our ski time, as they are ski hogs =)). We have the greatest memories already of family time at the lake.