router.js

ArticlesRoute = Em.Route.extend({
  model: function() {
    Article.find({page: 1});
    return Article.all();
    
  }
});

ArticlesController = Em.ArrayController.extend({
  currentPage: 1,
  
  loadMore: function() {
    this.incrementProperty('currentPage');
  },
  
  articleLoader: function() {
    Article.find({page: this.get('currentPage')});
  }.property('currentPage')
  
  isLoadingBinding: 'articleLoader.isLoading'
})



In the template:
<span {{action prevPage}}>Previous Page</span>
<span {{action nextPage}}>Next Page</span>