main.js

import React from 'react';
import ReactDOM from 'react-dom';
import { Router, Route, Link, browserHistory, IndexRoute } from 'react-router'

class App extends React.Component {
   render() {
      return (
         <div>
            <ul>
            <li>Home</li>
            <li>About</li>
            <li>Contact</li>
            </ul>
            {this.props.children}
         </div>
      )
   }
}
export default App;

class Home extends React.Component {
   render() {
      return (
         <div>
            <h1>Home...</h1>
         </div>
      )
   }
}
export default Home;

class About extends React.Component {
   render() {
      return (
         <div>
            <h1>About...</h1>
         </div>
      )
   }
}
export default About;

class Contact extends React.Component {
   render() {
      return (
         <div>
            <h1>Contact...</h1>
         </div>
      )
   }
}
export default Contact;