There are six toys you can use to play with your kitten. One of them you will have at the start of the game but the other five you must but from the store.
Butterfly
You have this toy at the start of the game. To play with it, you need to blow into the mic in your DS, and it will flutter around the room while your kitten chases it. If you stop blowing or if it gets stuck on top of the furniture, you can pick it up with the hand button in the bottom right corner of the touch screen.
Ball
With this fun toy you can do all sorts of things. You simply pick up the ball with the stylus (unless it is on the floor, in which you pick it up with the hand icon first) and you can throw it around the room. Your kitten will chase after it, and when it stops, pick it up with the hand icon. If you're playing with the ball in the garden you can even try and throw the ball over the fence or house, and you'll always get it back because you only have to press the hand icon.
Fish Pole
With this fun toy, your cats will chase the fish on the end of the pole. Using the stylus, you can move the pole around. If you hold it high up, your kitten will just, but leave it on the ground and your kitten will pounce on it.
Fancy String
This is similar to the Fish Pole. So, you can use the stylus to move the pole around and your kitten will chase the ribbon. Except with this toy, you can also move around the room by using the 
pad, and you can drape the ribbon over the furniture and watch your kitten having fun!
Wind-up Mouse
Using the stylus, you need to wind up the mouse. Do this by moving it in a circular motion anti-clockwise (basically, just follow the arrows on the touch screen) and the metre in the centre of the screen will fill up. When it gets to the top, stop winding and touch the metre. Now the mouse will zoom around the room uncontrollably as your kitten tries to catch it!
Dump Truck
There are two was to play with this toy: carry kitten and chase kitten. But both have the same controls:
: accelerate
: reverse
and 
: steer
: tip out your kitten or just lift the bucket
: honk the horn
If you select 'carry kitten', you will drive around the room with the kitten in the back of the truck, and it will meow every time you bash into something. Pressing the 
button in this mode will tip the kitten out of your truck and you will exit back to the menu.
Whereas if you select 'chase kitten' you will chase the kitten around the room, and it will meow if you crash into it. Pressing the button doesn't really do anything, except lift the bucket on the back of the truck. To exit this mode, you have to select the back button.
This is the most expensive toy, at $50, but it's definitely one of the best.