I just hope you're aware that small open powerboats are the most dangerous form of boating, statistically speaking. In Canada 37% of boat-drownings happen in small open powerboats. with only 4% being in sailboats, which are even marginally safer than paddle boats. http://www.redcross.ca/cmslib/genera...wn_english.pdf
In the US it's much more bleak with 7/10 boating deaths in US are in power boats under 21 feet. http://www.commanderbob.com/cbstats.html
and about a third of those open-motorboaters die of causes other than drowning (I don't even want to think about what those might be) http://www.uscgboating.org/assets/1/...Statistics.pdf
Though ultimately it's up to you and your kids. I see they aren't wearing life jackets on the boat, so perhaps safety isn't a priority. Though personally I'd rather see both you and them to have safe, long and happy lives. :-)
In terms of our kids, when they come of age i.e. 16 or as soon as they are ready afterwards, planning on getting them liveaboard sailboats, likely without engines -- they usually only cost about twice as much as a dinghy used. Then they'll be ahead of the pack in terms of having the resources to start their own lives and live independently.