Handle your rabbit every day. Rabbits that are handled (gently) often are rabbits that kick and scratch kids less, and are more fun to play with.
Let your rabbit have daily exercise. Rabbits are curious by nature, so a little jaunt around the house or in a fenced yard where they can't get out helps keep your rabbit entertained and enjoyable to have around.
Don't let anyone tease your rabbit. Sure, your kids may think it's fun to chase your pet rabbit to watch it hop around and try to escape, but this behavior is bad for your poor pets in general, and your rabbit too. Don't let kids tease your rabbit.
Watch other pets around your pet rabbit as well. While your pets may not mean any harm, a simple stomp, scratch, or curious nibble can frighten a rabbit and can even kill him on accident. Be particularly careful with dogs and cats around rabbits.
Don't leave your pet rabbit alone with very young children to play with. This way, you can keep your rabbit safer for years to come and know that your kids are handling their favorite pet carefully. Also, don't let your kids feed your rabbit anything that it should not have- their sensitive tummies can't handle a lot of starch, sugar, or carbs.