Science lessons don't have to be complicated or take extra resources. Here's a quick physics lesson that you can do while you are boiling pasta, rice, or potatoes for dinner. My children loved this chance to learn about how the weather is formed.
Pot with boiling water
Empty clear Plastic Container
How to do a weather demonstration while cooking dinner
Once the pot is boiling, grab your empty plastic container, and hold it over the pot, so that you to collect some steam. Be careful not to burn yourself on the steam! You'll want to collect a fairly substantial amount. While you're waiting for it to collect, use the time to ask your child whether the burner is putting energy into the water or taking energy out. (It's putting energy in.)
I was surprised at how easily my pre-schooler fielded that question. Next ask, "What is that going into the bottle?" (It is water in gas form, also known as "steam.")
When you think you have enough, cap the bottle and let your child put it into the refrigerator. Now ask, "Does the refrigerator take energy out of the steam in the bottle or put energy in? (The refrigerator takes energy out.)
After a few minutes, let your child take the bottle out of the refrigerator, and talk about what is inside. You should see some liquid water. Notice the little droplets forming on the side of the bottle, and how they gradually join up to form heavier droplets that roll down the side.
Why do they roll down the side of the bottle? (The force of earth's gravity pulls them down.) Why do the heavier droplets roll, but the lighter ones don't? (This is a tricky one that has to do with the polarity of water, feel free to leave it unanswered for now!)
Where do we see this phenomenon in nature? (This is the water cycle, and the currents also demonstrate how the sun's energy causes the wind.)
Why do this demonstration
This lesson is to familiarizes your child with the concepts of energy and states of matter and their changes. You can also address the concept of force.
More importantly, you are teaching your child to see the astounding detail that surrounds us at every moment.