You can't open multiple lists at the same time.

[gbenavid]

Each time we press the button that triggers clicked() as seen in ShoppingList.js on line 26:

  render () {
    const { name, user, handleDelete, appendTo } = this.props;
    return ( 
      <article>
        <h3>{ name }</h3>
        <button onClick={ handleDelete }> Delete </button>
        <button onClick={()=> this.clicked(appendTo, name)}> Select </button>
        {
          this.state.childVisible ?
            <ShowItems  user={this.props.user} 
                        appendTo={appendTo}
                        content={this.props.content}
            />
          : <span></span>
        }
      </article>
    );
  }

The function toggles the show/hide state of the element.
And I'm not 100% sure of the toggleItems method.... let's look deeper into this...

  clicked(key, marketName){
    this.setState({childVisible: !this.state.childVisible}); /* We need to only toggle for the specific element with the same id as the item being clicked. */
    this.props.toggleItems(key, marketName);
    // this.setState({itemsToggled: !this.state.itemsToggled});
  }

The end functionality is a bug in the UI that manipulates the previous lists that are opened if multiple lists are selected.