Kershaw Leek has a slide lock.
It does, but you have to remember to slide it close everytime you close the knife. Besides, it is an assisted knife with a needle thin tip, which could be much more dangerous if letf unlocked than any non-assited knife.
Anyway, to the OP. I don't own any guns, but I read a lot here about gun safety, procedures, teaching kids what to do / what not to do, etc. Knives are not different and, in a way, you should be carefull with where you leave them and who can grab them. Also, teaching your kids about knives and that they are sharp, is the best investment in safety you could get.
Right now I have a 5 year old daugther that is very veeeeeeeeeeeery familiar with knives. We live in an urban environment, so it is not that she had been arround a farm chopping chicken heads off for her whole life. BUT once she got curious about kitchen duty, cooking, etc. I introduced her to knives. She chops veggies, peels potatoes, dices fruits for her oatmeal, etc. She has cut herself a couple times (superficial) so she knows it hurts and is carefull. She sometimes asks me about my pockets knives (she is used to me always having one in the pocket) and I let her fondle them, always warning them that they are sharp. She doesn't pay much attention to them because it is not a novelty or something forbidden, even if they have bright colors.
Mikel