The promise of free airfare can be very compelling, but before you buy any bundled trip, you need to do the math to make sure you can’t get it for less if you book on your own. Let's see how the components break down:

• Airfare: When we price-checked Alaska Airlines airfares for a family of four traveling from Seattle in late February, we found regular fares starting at $300 per person and a  few limited-time fares starting at $100. We comparison shopped at Kayak.com and Orbitz.com, and found some $100 and $120 fares for several airlines, including Alaska Airlines—which are great deals.
• Lodging: The Alaska Airlines package includes lodging, and taps a Buy Three Nights, Get Two Free deal at the three Disneyland Resort hotels (Grand Californian, Disneyland Hotel and Paradise Pier). This translates to a 40% savings on your lodging.
• Disneyland tickets: The deal automatically adds Disneyland tickets, such as the 3-Day Hopper (good for both Disneyland and California Adventure) for each family member.  When we tried buying 3-day hoppers for a family of four through Disney's web site, the latest sale (good through April 29) brought the price down to $596—without the deal, they would total $776.

Once the elements in your package are bundled together, your final price depends on which hotel you choose. When we checked rates for a 5-day trip for our Seattle family of four, the total price came to $2,563 if staying at the classic Disneyland Hotel (the mid-priced choice of the three properties). Of that price, $592 is for the 3-day Park Hoppers for all four family members—a teeny break compared to Disney's deal.

Deal or no deal? There are many ways to snag a Disney deal these days. No doubt, the airline's Kids Fly Free package saves you a nice chunk of money. Many families will find tremendous value in the convenience of booking airfare + hotel + tickets in one tidy bundle. Can you beat the price by booking the elements on your own? Quite possibly, since Disney is offering its Two Nights Free for basically the same dates without any airfare requirements. Everything depends on whether you're willing to invest time hunting down a dirt cheap airfare. For example, if our Seattle family of four was able to snag $100 airfares on Kayak.com, their independently-booked five-day vacation at the Disneyland Hotel would total about $2,400—about $160 cheaper than if booked with the Alaska Airlines package. 

When booking the Alaska Airlines deal online, just click on the participating hotels after entering your dates. Or you can book through Alaska Airlines by phone at 800/468-2248. 

Note: Finding dates that work for you can be frustrating. There is a different set of blackout dates for the aifare and hotel components, which creates a patchwork of spotty availability if you want to take advantage of both deals. Blackout dates for air travel are: February 18-19 and 22; March 19, 21, 26, 28; and April 2-5. For the hotel deal, blackout dates are January 7-17, February 12-14 and March 28-April 10.

For both deals, you must book your trip by April 1, 2010. For the Kids Fly Free offer, you can travel January 5 through April 30, 2010. For the Buy Three Nights, Get Two Free offer, you must arrive at your hotel by April 29 at the latest.