In America, we place such a huge value on measurable learning that we forget some times that children are learning every time they seem to be "just playing". There are wonderful ways to support the naturally scientific and inquisitive mind of a preschooler as is demonstrated in an excerpt from the Cedarsong Forest Kindergarten monthly newsletter:
"As the weather warms up, we have gotten out the paintbrushes several times to use with our black charcoal “paint”. The children love to crush up the charcoal from our firepit and add just the right amount of water to make a useable paint. This activity provides a great opportunity to talk about what charcoal is and how it is actually a prescribed medicine! The children not only covered all of the sitting logs with the black paint, some even painted their faces with it. We are also noticing different colors of dirt and collecting and comparing them, wondering about why they are different. This leads to talks about how soil or dirt is formed and what it is made of.
There has been a steady enough rain during the month to keep the water level in our puddle fairly high. The kids enjoy measuring the depth of the puddle after guessing how deep they think it is. We use a stick that is painted different colors at various levels to measure and see if their hypotheses are correct. It is a loose measuring, like “do you think the water level will be up to the top of the purple, red or blue section of the stick?”; the colors are about 6 inches apart.
We have also been talking about volume. The kids have created a secondary puddle by digging a hole and then building a dam to hold back the water they pour. When we have full buckets, we ask before pouring: “Do you think this full bucket will cause the puddle to overflow the dam?” All the kids add their ideas and then we pour the bucket and watch. They are all so intent! One of the children will then announce whether or not that volume of water was enough to overflow. If not, we get another and try the whole experiment over again. The children really love the process as much as the result."