It's easy to want to protect our kids, or over-protect them. (I would know, my kid is the only one wearing a helmet on her scooter on the block...)
Sometimes that urge to protect can hinder their development. I've seen 3 and 4 year olds using forks with rounded ends meant for much younger children, which can be really frustrating for them.
As Maria Montessori says kids come from, "Help me do it myself."
Here are a few knives we have found most helpful and notes about using knives with kids.
1) always supervise a child with a knife
2) eat family meals together so they can watch you use a knife and learn from you
3) make the task appropriate. Your 3 year old can't cut steak, but she can cut bananas.
4) watch that the child can master a skill before moving on.
5) consider kids' cooking classes. We attended a fun one on knife skills when M was just 4. She learned about curling her fingers under like a "bear claw." When I help her cut, all I do now is say, "Bear claws!" and she tucks her fingers under.
6) have the right tool for the right job (see below)
7) be sure the child is stable-standing or seated
8) be sure the cutting area is stable, use a just-dampened paper towel under a cutting board so it won't slip...
Remember, each child is different in their interests and skills. One child may be more adept at using the knife than another. Watch your child and see if any of the options below might work..
Lettuce knife. Great for kids helping with meal prep. Here is M at 4 cutting green beans. A mom at school told us about this knife. Her son has been chopping veggies since he was three. (He is way better than M at this...)
Ikea knife, nice handle, great starter knife. There is some serration, so be sure to monitor use. Good for cutting bananas, soft fruit...