Edit in JSFiddle

// This is more complex example that uses two components -
// a service chooser form, and the individual services inside it.


var ServiceChooser = React.createClass({

    getInitialState: function(){
        return { total: 0 };
    },

    addTotal: function( price ){
        this.setState( { total: this.state.total + price } );
    },

    render: function() {

        var self = this;

        var services = this.props.items.map(function(s){

            // Create a new Service component for each item in the items array.
            // Notice that I pass the self.addTotal function to the component.

            return <Service name={s.name} price={s.price} active={s.active} addTotal={self.addTotal} />;
        });

        return <div>
                    <h1>Our services</h1>
                    
                    <div id="services">
                        {services}

                        <p id="total">Total <b>${this.state.total.toFixed(2)}</b></p>

                    </div>

                </div>;

    }
});


var Service = React.createClass({

    getInitialState: function(){
        return { active: false };
    },

    clickHandler: function (){

        var active = !this.state.active;

        this.setState({ active: active });
        
        // Notify the ServiceChooser, by calling its addTotal method
        this.props.addTotal( active ? this.props.price : -this.props.price );

    },

    render: function(){

        return  <p className={ this.state.active ? 'active' : '' } onClick={this.clickHandler}>
                    {this.props.name} <b>${this.props.price.toFixed(2)}</b>
                </p>;

    }

});


var services = [
    { name: 'Web Development', price: 300 },
    { name: 'Design', price: 400 },
    { name: 'Integration', price: 250 },
    { name: 'Training', price: 220 }
];


// Render the ServiceChooser component, and pass the array of services

ReactDOM.render(
    <ServiceChooser items={ services } />,
    document.getElementById('container')
);

<script src="https://facebook.github.io/react/js/jsfiddle-integration-babel.js"></script>

<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

* {
    padding:0;
    margin:0;
}

html{
    font:14px normal Arial, sans-serif;
    color:#626771;
    background-color:#fff;
}

body{
    padding:60px;
    text-align: center;
}

h1{
    font-size:18px;
    margin-bottom:20px;
}

#services{
    list-style: none;
    display: inline-block;
    width: 340px;
    text-align: left;
}

#services p{
    display: block;
    padding: 15px 20px;
    background-color: #F8F8F8;
    color: #7B8585;
    margin-bottom: 3px;
    position: relative;
    cursor: pointer;
    
    transition: 0.3s;
}

#services p b{
    position: absolute;
    right: 28px;
    line-height: 16px;
    width: 100px;
    color: #808787;
    text-align: right;
}

#services p:hover{
    background-color:#d8f2f1;
}

#services p.active{
    color:#fff;
    background-color:#41c7c2;
}

#services p.active b{
    color: #fff;
}

#total{
    background: none !important;
    cursor: default !important;
    padding-top: 10px !important;
}