New Twiddle

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  init() {
    this._super(...arguments);
    this.items = [
      { id: 1, name: 'first' },
      { id: 2, name: 'second' },
      { id: 3, name: 'third' },
      { id: 4, name: 'fourth' }
    ];
    this.selectedItems = [];
  },
  
  actions: {
    valueHasChanged(item, isChecked){
      if (isChecked) {
        this.get('selectedItems').addObject(item);
      }
      else {
        this.get('selectedItems').removeObject(item);
      }
    }
  }
});

application.template.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
<table>
<tr>
	<th>Selected</th>
  <th>Items</th>
</tr>
{{#each items as |item|}}
	<tr>
    <td>
      <input type="checkbox" onchange={{action (action "valueHasChanged" item) value="target.checked"}}>
    </td>
    <td>{{item.name}}</td>
  </tr>
{{/each}}
</table>
<br>
<br>
<p>Your Selected Items:</p>
<ul>
  {{#each selectedItems as |item|}}
    <li>{{item.name}}</li>
    {{else}}
    <em>No items selected</em>
  {{/each}}
</ul>

twiddle.json

{
  "version": "0.5.3",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.3.1",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.3.3/ember-data.js",
    "ember-template-compiler": "2.3.1"
  }
}