Q:

how to return values from actions in emberjs

how to return some value from actions?? 
I tried this:
var t = this.send("someAction", params);

...

    actions:{
      someAction: function(){
          return "someValue";
      }    
    }

A:

actions don't return values, only true/false/undefined to allow bubbling.  define a function.
Ember code:
  send: function(actionName) {
    var args = [].slice.call(arguments, 1), target;

    if (this._actions && this._actions[actionName]) {
      if (this._actions[actionName].apply(this, args) === true) {
        // handler returned true, so this action will bubble
      } else {
        return;
      }
    } else if (this.deprecatedSend && this.deprecatedSendHandles && this.deprecatedSendHandles(actionName)) {
      if (this.deprecatedSend.apply(this, [].slice.call(arguments)) === true) {
        // handler return true, so this action will bubble
      } else {
        return;
      }
    }

    if (target = get(this, 'target')) {
      Ember.assert("The `target` for " + this + " (" + target + ") does not have a `send` method", typeof target.send === 'function');
      target.send.apply(target, arguments);
    }
  }

