[kyteacher]

I'm looking for strategies to teach for estimating in third grade. I don't even know what these are other than carefully observing what you are estimating.

Any ideas?

[mathtch]

I teach 5th grade and when I think of estimating strategies I think of

compatible numbers: especially useful for division- finding numbers that work well together

front-end estimation: useful for a quick estimation

rounding to the greatest place value of the smallest number.

[Mrs. C]

A couple years ago I came across this idea in the Everyday Math newsletter and we implemented it school-wide. Each month we have a display cabinet in our hallway decorated with some theme. There is a medium-sized clear glass apothecary (sp?) type jar with lid. In it are items. Then each classroom gets to decide on their estimate and turn it in. The closest estimate gets what is in the jar.

Ideas that we have used in the past: pencils, erasers, UNO playing cards, dominos, chess pieces, puzzle pieces, tootsie rolls, pencil toppers, smarties, etc. Students look forward to seeing what is in the jar each month. We keep track in our classroom and use the previous items for comparison and to help with our guess. That is the main strategy we are focusing on with this project - I know ____, so how can I use it?

[BelleBelle]

I also use an estimation jar in my classroom to reinforce and master maximum, mimimum, range, median, and mode.

Every Friday I pass out a post-it to each student. One student walks around with the jar and allows students to glance at it without touching. Then once they have decided on an estimation they write it down (along with their name) then I have call students to go up to the dry erase board and stick their estimation post-it up. The students must put their estimation in correct number order independently (this is another mastery standard).

Once all estimations are in, the student who walked around with the jar gets to dump the jar and everyone counts the items in the jars by 5's, 2's, 3's. It is such an great way to practice counting by different numbers. Very repetative. Then as a class we see who was closest and that person gets to take home the jar to fill with items of their choice. We then take all the data and identify maximum, mimimum, range, median, and mode. After that we create a bar graph with the estimations.

The students love the activity, it helps to reinforce the skill on a weekly basis and allows the students to enjoy learning.