app.js

var ListItem = React.createClass({
    getInitialState : function() {
        return { selected : false }
    },
    onSelect : function(e) {
        this.setState({ selected : !this.state.selected });
    },
    render : function() {
        console.log(this.state.selected);
        return (
            <li onClick={this.onSelect} className={(this.state.selected) ? "selected" : ""}>
                {this.props.user.firstname} {this.props.user.lastname}
            </li>
        )
    }
});

var List = React.createClass({
    render : function() {

        var users = this.props.users.map(function(user) {
            return <ListItem user={user} />
        });

        return (
            <ul className="list">{users}</ul>
        );
    }
});


var users = [];
for(var i = 0; i < 40; i += 1) {
    users.push({
        firstname : faker.name.firstName(),
        lastname : faker.name.lastName(),
        email : faker.internet.email()
    });
}

React.render(
    <List users={users} />,
    document.body
);