import React, { Component } from 'react';

export default class App extends Component {
  render() {
    return (
      <h1>Hello React :)</h1>
    );
  }
}

import React from 'react';

const App = React.createClass({
  render: function() {
    return (
      <h1>Hello React :)</h1>
    );
  }
});
export default App;

Use createClass instead of ES6 classes
Use createClass instead of ES6 classes

Most of the React docs use createClass. It will be easier for students
to follow the docs.
