How to carry out a science day at school?

My husband came to my classroom one day and did a simple experiment with my Kindergarten that older children could do on their own. He used a spoon and a tiny lightbulb to make a light. Of course, he also used wire and a battery. The kids were amazed, and every one of them wanted to try it. You can use an overhead projector to let the kids draw silhouettes of each other showing how an eclipse works. You can put cream into a baby food jar and let them shake it to make butter. Drop some thinned paint onto a paper and let them blow on it with straws. Or give them coffee filters and eye droppers. Give them an eye dropper and experiment to find out how many dropperfuls it takes to fill a very small container. Make ice cream by rolling tin cans. They love that one. Give them a basin of water and a group of simple objects and let them predict which objects will float and which won't. Science is so much fun, and that's what you need to get kids more involved.