# Guess How Much Water? Estimation Jars

Back in October, I wrote about my Marker Estimation Jars. There are lots of things that can be put in an estimation jar, but what about volume estimation jars?

For estimating volume, I used sand in the jars and water. Like I did with the marker jars, I used 4 jars to show children different amounts. Three of the jars are used to gain knowledge about what’s inside and how much space it takes up, and the last jar is for guessing. {By the way, these are clear plastic jars from Walmart’s kitchen gadget department.}

For these sand jars, I put 1 measuring cup of sand in the first jar, 2 cups in the second jar, 3 cups in the third jar, and 4 cups in the fourth jar. Since that is a little too obvious for guessing, I taped the numerals to the 1st, 2nd, and 4th jars, and put a question mark on the 3rd jar. That way, they weren’t just counting “1, 2, 3, … 4”. I used a 1 cup measurer, but you could also use a half measuring cup, 1/3 measuring cup, or 1/4 cup. I used Jurassic Sand that we use in our sensory table since we have it in large quantities (not an ad, just a recommendation). Colored art sand would be pretty, too.

For these water jars, I put one half cup of water in the first jar, 3 half cups in the second jar, 6 half cups in the third jar, and 9 half cups in the fourth jar. The children will look at the numbers on the lids of each, and make a guess at how much water they think is in the fourth jar. This activity can be repeated by using different amounts of water.