Play is one of those areas where more is better, providing, of course, that parents remain sensitive to the baby's mood. The more space a baby has to play in, the more she will explore; the more novel things there are to play with, the more curiosity she will show about the rest of the world; the more time parents spend playing with her, the more time she will spend playing on her own.

Mood, however, is everything. Mood is the reason tickling is greeted at 1 in the afternoon with great belly laughs and at 3 with wails. Here are some suggestions on setting the mood and other ways to have a good time:

I got rhythm. We all are subject to natural rhythms: physical biorhythms and the rhythmic structure of the day (awake, eat, work, sleep, etc.). The younger the child, the more important is rhythm in establishing good play experiences. When you start an activity, build it in intensity, gradually lower the intensity, stop and allow the child to rest a little, then go on to another game. Alternate the rhythm of games also: Active play could be followed by a watching or listening game, or an interaction game by a game the child plays alone.

Babies have typical waking-sleeping patterns, which also determine mood. Once a parent knows the child's pattern (which unfortunately seems to change shortly after you've figured it out), play should be geared for the middle of the waking period, with quiet activities in the beginning and end (diapering, feeding, bathing, free play, etc.) Most likely, very active play just before bed doesn't tire out the baby but excites his nervous system, making it more difficult to fall asleep and resulting in more restless sleep.

The state of a baby's digestion makes a difference, too. A very full or very empty baby isn't interested in fun and games.

Listen to your baby. Read cues for likes and dislikes, and adapt your behavior accordingly. Don't push a child to do something she doesn't want to.

Unhappy responses may be the result of a variety of things. The child may be tired, hungry, overfed, ill, fearful of the activity or toy or person playing with him, bored, or overstimulated, or he may want to do something else. Assess the situation and either make modifications or let the child have some quiet time. A rejection by a baby doesn't mean he doesn't want to play, he just doesn't want to play now. Don't take it personally.

Activate your baby. Play that requires the child, not the parent, to perform the motion or that elicits an active response is activating. Play in which the child is a mere spectator or is being manipulated without any response required on her part is passive.

Remember that in the first two years, a baby's strongest systems are those for touch and movement. Watching and listening games, although important for other reasons, usually are not activating; in fact, activating games in the early years can benefit vision and hearing later on. You want, gently, to get the baby to like to think and do things for himself.

Get down. Sit on the floor whenever possible, whether watching TV, reading, folding clothes, talking, or whatever. Being on the same level as your baby will inevitably lead to play and give the child a secure sense of having you accessible.

No right or wrong way. Babies discover the world in different ways from adults, but since they can't tell us that, we often make adult assumptions for them. Research shows that babies organize the world according to what it does: what is movable, eatable, touchable, breakable, bounceable, etc.

An adult who assumes a baby is trying to figure out how to stack blocks and so does it "the right way" may in fact be interfering with a completely different concept the child was working on. Parents should demonstrate ways of doing things but not as the only way they can be done.