Our classroom assistant assembled this activity as part of her ongoing Montessori training.  Added to the Math area of the classroom is this ‘Guesstimation Jar.’

The children have a look to see how many spiders they think are in the jar and write down their ‘guesstimate’ on a slip of paper.  These papers are collected in the orange bowl on the right side of the tray.  Very soon, we will gather the children, read the guesstimates, and then count how many spiders are actually in the jar.  Our plan is to vary the contents according to seasons or holidays.  What a fun way to get the children making estimates and writing numbers!