serrated is the one with teeth. It is safe, you can rub it along your skin and not get cut. having said that I teach him knife safety so I won't let him do that to his skin, I treat it as though it is SHARP so that when it comes to a sharp knife he will already know the rules and dangers. I would not allow him to use it alone, or walk around with it, like I wouldn't allow it with a sharp knife. Up to now (I think we've had this about a year?) I still work with him hand over hand. he stands on a chair and I stand right beside him, on his left, I put my right arm (we are both right handed) around him and my right hand goes over his right hand on the knife. I put my left hand over his left hand and show him how to hold the vegetable, ensuring his fingers and thumb are tucked in which is not so easy for LOs just yet. He puts no pressure on the knife until I tell him to cut, then I feel his muscles and how much he is taking control of the knife (you have to use a sawing action with it but it is surprisingly versatile, accurate). So it is very much team work at this point for us. I've seen LOs with similar knives at toddler group not so tightly supervised, just using it themselves but for 2yo or 2.5yo it's a pretty difficult thing to do alone...but I actually want to be this close, I don't want him to know the knife is safe iyswim. I haven't taught him to keep his hands off the board, instead I have taught him where his hands need to go when chopping, so it is on the food to steady it and out of the way of the knife. We use a cheese grater and potato peeler in the same way. We also have the duck scissors which are not used so much and not so versatile, we just chop spring onions with them, but the action has really helped him come along with using scissors which he can't quite do but is improving.
