This fun and easy activity uses cheap items or items you already have on hand. Challenge kids to use their spacial awareness to determine how many items are in a jar. Check out out all of our estimation jar ideas below.

Supplies for Estimation Jar

• A Jar
• A lot of one object
• small pieces of paper
• An answer box

The Setup

Fill a jar to the top with one objects.  It can be anything; cotton balls, marbles, toothpicks, etc.  Count the items as you put them into the jar (this can be very daunting but you can do it!)

Then, write the total number of items on a piece of masking tape and put the tape inside the jar of the lid. Put the lid back on, tight, very tights so you don’t get any peekers.​

​How To

​Set out the jar for children to examine.  Ask the kids to use there problem solving skills to determine how many objects are in the jar.  When the children have an educated guess have them write their answer down and put it in the answer box or paper bag.

When I do this activity I leave it on the table Monday-Thursday.  On Thursday after my After School Program wraps up I check the answer box.  I write down who was the closest and on Friday they get a small prize from the box. 

Below are some Estimation Jar activities.  What else could you use?  Comment below with your ideas.

If you enjoy estimation jar activities you can take this activity a step further with: Estimation Jar – Weight on the Moon. Using our weight on the moon reference sheet, have kids guess how much things weigh in space.

You may also like What’s the question. A quick and hilarious writing activity for kids. Give them a statement and have them develop the question.