Your kittens are just venturing out into life and are encountering the world and its realms of interest for the first time. In just the first few weeks of your kittens life you are sure to learn and see first hand the real meaning behind curiosity being so strongly linked to the feature of cats. Kittens even more so than fully grown adult cats tend to let their new encounters ravish their attentions and they are easily caught up in the wonder of anything new, anything that moves, smells and tastes new to them.
Kittens are intrinsically playful and this playfulness is more than just curiosity and liveliness. Playing with you, with other kittens and with a ball, kittens toy or piece of scrunched up paper is vitally important to any kittens development. Through play kittens will learn, they will be able to keep dexterous while strengthening their growing muscles and they will also be able to build up a relationship with you and their near animal counter parts that will lead to strong bonds and good relationships.
Encouraging your kittens to play and spending time playing with them will help to direct their energy, and need to learn, in the right directions. Kittens learn fast and grow up just as fast, with a playful and happy kittenhood you can be sure that your kittens will grow up to be wonderfully reared and loving adult cats.