We bought all of the Hot Wheels Kidpicks accessories - Track Curve, Booster, Loop, Launcher, etc. Christmas morning when our 3 & 6 y/o girls woke up they discovered race tracks all over the living room left by Santa and cars in everyone's stockings. The entire family had a lot of fun all morning racing and trying not to crash. The curve track is a necessity unless you're just going to drag race down the hall. And be prepared to buy 2 or 4 box kits. The kit has 4 pieces and only 2 of them have the tongue connector that fit into the standard track. The others have clip shapes that only snap into each other. So you can only make 1 180/90/45 degree turn from a box. All of the pieces should have been designed with tongue connectors in my opinion, but how else could Mattel get more money out of you. So when you order, be sure to buy either 2 or 4 Track Curves otherwise you won't be able to connect the ends of your track to make circles and ovals.