Comparing and ordering decimals.... ugh. My students always balk at this topic. They think it is hard. They think it is impossible. They think I am a horrible person for making them do it! However, I think I may have broken through the mind block today!
We worked on a paper entitled "A Reptilian Recluse" ( see below)
When I introduced it by reading the clues for Row A, there were groans. However, I explained that we can break the curse of comparing and ordering decimals if we use a graphic organizer.... a T-Chart! So, we made a T-Chart on the notebook paper and we wrote each of the decimal numbers onto the chart by LINING UP THE DECIMAL points!
Now, we fold over the paper and look at the whole number.
This was no help, they were all the number 35. So we move the edge of our paper over so that we can see the tenths. This time we were able to place the decimal numbers in order from least to greatest JUST by using the tenths place. Once we had done this, the rest was easy!
The clues for Row A were:
- Circle the number that is least
- Since we had already put them in order from least to greatest, we were home free! The answer was 35.172
- Draw a line above the number that is less than 35.4 and greater than 35.2
- We folded our paper to hide all the digits except the whole number and the tenths place. We looked for the digit that was smaller than 4, but greater than 2.... we needed a 3! The answer was 35.309
- Underline the number that is between 35.5 and 35.75
- This time we began by adding a "0" to 35.5 making it 35.50 (an equivalent decimal). Now it was easy to compare our numbers. We folded our paper over to show only the whole numbers and the digits through the hundredths place. We needed something greater than 50 but less than 75. The answer was 35.691
- Write an X beside the number that is greatest.
- Since we had already put the numbers in order from least to greatest we were able to find it easily! The answer was 35.899
After completing the example together, the tables worked together to solve B, C, and D. I rotated from table to table to answer questions and help as needed.
There is a homework assignment tonight: edmodo.com