I'm following the sample code in this particular Trailhead.   I've even "copied" the code itself, and still when I go into Preview and try and create an expense; nothing happens.  No data is being posted back to Expense__c.

Even the debug shows the data is getting captured



If that's hard to read its:
Create expense: {"sobjectType":"Expense__c","Name":"Test","Amount__c":100,"Client__c":"ABC","Date__c":"2016-11-02","Reimbursed__c":false}
components/c/expenses.js:44 Expenses before 'create': []
components/c/expenses.js:47 Expenses after 'create': [{"sobjectType":"Expense__c","Name":"Test","Amount__c":100,"Client__c":"ABC","Date__c":"2016-11-02","Reimbursed__c":false}]

I've got to be missing something somewhere.

Here's the code:

expensesApp.app

<aura:application extends="force:slds">
    
    <!-- This component is the real "app -->
    <c:expenses /> 
	
</aura:application>

expenses.cmp

<aura:component >
	
    <aura:attribute name="expenses" type="Expense__c[]"/>
    
    <aura:attribute name="newExpense" type="Expense__c"
     default="{ 'sobjectType': 'Expense__c',
                    'Name': '',
                    'Amount__c': 0,
                    'Client__c': '',
                    'Date__c': '',
                    'Reimbursed__c': false }"/>
    
    <!-- PAGE HEADER -->
    <div class="slds-page-header" role="banner">
    	<div class="slds-grid">
        	<div class="slds-col">
            	<p class="slds-text-heading--label">Expenses</p>
                <h1 class="slds-text-heading--medium">My Expenses</h1>
            </div>
        </div>
    </div>
    <!-- / PAGE HEADER -->
    <div class="slds-col slds-col--padded slds-p-top--large">
    
        <div aria-labelledby="newexpenseform">
        
            <!-- BOXED AREA -->
            <fieldset class="slds-box slds-theme--default slds-container--small">
            
                <legend id="newexpenseform" class="slds-text-heading--small slds-p-vertical--medium">
                	Add Expense
                </legend>
                
                <!-- CREATE NEW EXPENSE FORM -->
                <form class="slds-form--stacked">
                
                    <div class="slds-form-element slds-is-required">
                    	<div class="slds-form-element__control">
                        	<ui:inputText aura:id="expname" label="Expense Name" 
                            	class="slds-input" 
                                labelClass="slds-form-element__label"
                                value="{!v.newExpense.Name}"
                                required="true" />
                        </div>
                    </div>
                    
                    <div class="slds-form-element slds-is-required">
                    	<div class="slds-form-element__control">
                        	<ui:inputNumber aura:id="amount" label="Amount"
                            	class="slds-input"
                                labelClass="slds-form-element__label"
                                value="{!v.newExpense.Amount__c}"
                                required="true" />
                        </div>
                    </div>
                    
                    <div class="slds-form-element">
                    	<div class="slds-form-element__control">
                        	<ui:inputText aura:id="client" label="Client"
                            	class="slds-input"
                                labelClass="slds-form-element__label"
                                value="{!v.newExpense.Client__c}"
                                placeholder="ABC Co." />
                        </div>
                    </div>
                    
                    <div class="slds-form-element">
                    	<div class="slds-form-element__control">
                        	<ui:inputDate aura:id="expdate" label="Expense Date"
                            	class="slds-input"
                                labelClass="slds-form-element__label"
                                value="{!v.newExpense.Date__c}"
                                displayDatePicker="true" />
                        </div>
                    </div>
                    
                    <div class="slds-form-element">
                    	<ui:inputCheckbox aura:id="reimbursed" label="Reimbursed?"
                        	class="slds-checkbox"
                            labelClass="slds-form-element__label"
                            value="{!v.newExpense.Reimbursed__c}" />
                    </div>
                    
                    <div class="slds-form-element">
                    	<ui:button label="Create Expense"
                        	class="slds-button slds-button--brand"
                            press="{!c.clickCreateExpense}" />
                    </div>
                    
                </form>
                <!-- / CREATE NEW EXPENSE FORM -->
                
            </fieldset>
            <!-- / BOXED AREA -->
        </div>
    </div>
    <!-- / NEW EXPENSE FORM -->
    
</aura:component>

expensesController.js

({
    clickCreateExpense: function(component, event, helper) {

        // Simplistic error checking
        var validExpense = true;

        // Name must not be blank
        var nameField = component.find("expname");
        var expname = nameField.get("v.value");
        if ($A.util.isEmpty(expname)){
            validExpense = false;
            nameField.set("v.errors", [{message:"Expense name can't be blank."}]);
        }
        else {
            nameField.set("v.errors", null);
        }

        // ... hint: more error checking here ...

        // If we pass error checking, do some real work
        if(validExpense){
            // Create the new expense
            var newExpense = component.get("v.newExpense");
            console.log("Create expense: " + JSON.stringify(newExpense));
            helper.createExpense(component, newExpense);
        }
    }
})

expensesHelper.js

({
    createExpense: function(component, expense) {
        var theExpenses = component.get("v.expenses");
 
        // Copy the expense to a new object
        // THIS IS A DISGUSTING, TEMPORARY HACK
        var newExpense = JSON.parse(JSON.stringify(expense));
 
        console.log("Expenses before 'create': " + JSON.stringify(theExpenses));
        theExpenses.push(newExpense);
        component.set("v.expenses", theExpenses);
        console.log("Expenses after 'create': " + JSON.stringify(theExpenses));
    }
})

Thanks to all.