Give your children a chance to repeat experiences, to practice skills, to deepen their understanding. Talk with your children. Encourage your children to talk about their experiences. Listen to them, talk about what they observe, think, and feel. Ask questions, especially those with more than one answer.
Science is all about searching for answers.
Observe and experiment together to find answers to your children's questions. Go to the library, use other resources. Start by looking for information together, and soon your children will try it on their own. Enthusiasm is catching. Let your children see that you have questions about the world, too.