What is the greatest risk; children using knives or children not using knives? Does the risk lie in teaching a child the skills required to use a knife or is the risk in not allowing a child to use a knife and denying them important life skills?
As a Montessori parent my children started using knives as toddlers. They started with a butter knife (or other dull round tipped knife and also vegetable choppers) to cut something soft like a banana. As the child gets older the knife gets sharper and the food gets harder or more difficult to cut.
I advocate for real knives and real food however starting with a soft food and a dull knife allows for the child to develop their skills gradually.
At four years old my child can competently use a sharp knife. He holds both the knife and food safely. The knife is aways small so that he can handle and control it. He will let me know if he needs help.
Children need risk. Risk challenges them and keeps them alert, it makes them responsive and teaches consequences. However parents are often so afraid, it's to the detriment of their children. Maria Montessori would call this oppression.
Children are capable. But they need our help. We need to enable and empower them.
Children need to learn new skills, real life skills. Once they are capable in one area they will have the confidence to work and excel in other areas. When they complete real work there is a powerful sense of accomplishment which can build the child's sense of self. Children need work and accomplishments they can be proud of.
Children also need to feel trusted, in turn they can begin to trust themselves and trust those around them. They then too begin to believe in themselves and see what they are truly capable of.
If taught with care and patience children can become very capable and skilled. Children can make a real contribution to their family and community. A child's day doesn't need to be all about fun and play. Children can learn to chop food to eat. They can make their own snack, contribute to a family meal or community celebration. They can become independent but also help others. They can use their skills to make a contribution to something greater than themselves.
Using a knife can improve hand control. It can build hand and arm strength and fine motor skills.
With the same of amount of attention they can also learn to use a grater or perhaps even a peeler (or other dangerous things).