I have 2 kids, currently 8 and 10. Both are fickle when it comes to the question "what do you want for Christmas?".
Last year I decided to buy everything online (avoid the lines and parking). I bought a Amazon Prime Membership and this is how it saved my Christmas:
Free 2-day shipping (no min $):
December 20 my then 7 year old says he can't wait for Santa to bring him the "marble game" he asked for. This was unfortunately the first I heard of this gift. I quickly found the game online and thought "there is no way it will get here by Xmas Eve". Not only did I get the game before the 24th, I got it the next day! My son was so happy Santa remembered.
Kids change their mind on what they want? No problem - free returns. I get it within 2 days and don't have to worry about not getting it. Kid wants something else, I return item no questions asked.
Early Access to Lighting Deals:
Last year my son wanted the Nerf Centurion - at the time it was $99 CAD in the stores. At 20% off that's a tall order (even for Santa). What pops up in my Amazon Prime Deals one day in November? A Nerf Centurion for $35.99 CAD (with free, 2-day shipping). Boom.
One, $5 Item? - no shipping
Want Nerf darts to go along with it, but forgot to order them with the gun? No problem - Prime Members get free shipping regardless of amount spent! That's right, no more topping up your cart with $5 more dollars you don't want to spend just to get that free shipping! I've ordered Band-aids, paper plates, Cascade Dish Tabs, batteries, felt pens, even garbage cans - all on their own orders for less than $25. I also use my membership for work purchases and will sometimes place 3 orders on the same day.
There are other benefits I don't take advantage of (20% off diapers - plus diapers delivered to your home! and free unlimited photo storage in cloud. Give it a try and save your Christmas.