TakeMeFishing.org just published a quick guide to getting a kid handy with a fishing rod. Muskegon River Lodge pro-tip: Avoid buying those cartoon character licensed mini-rods that come packaged with line and lures, etc. They don’t last and they’re not fixable. You’re welcome.
Excerpts (and go to link in the text for more tips:
Here’s the most practical and helpful way of how to teach a child to cast a fishing rod: practice first on land in an open field, not while also trying to catch fish on the water. Teaching a child to cast onshore gives him/her time to develop timing and coordination, and you can build up to increasing accuracy by giving them distances to achieve (start short) and broad target areas to shoot for.
Set the gear up for left- or right-handed use, whichever is appropriate. Let them do what comes naturally to them.
Use practice casting plugs, which are aerodynamic weight-forward rubber or plastic objects without hooks, to start and to gain proficiency.