# Math Update!

For the last few weeks, we have created graphs and made comparisons during our math switch time.  As our expertise grew, so did our graphs! Instead of comparing just two groups of objects, most of our graphs now compare three categories of data, like the graph below:

We are always trying to make comparisons between the data in each category (group) by finding the MAGIC NUMBER. With three groups it’s a little harder to find the difference especially when comparing the top category of data with the bottom category of data. If we use a pencil to cover up the extra information, finding the MAGIC NUMBER is a breeze.

The rest of our time was spent solving comparison stories. Our first graders learned a new strategy called: COMPARISON BARS. Comparison bars are a visual tool for solving stories in which two amounts are compared and the difference (magic number) is either known or unknown. Check out the examples below:

Thank you for helping your child use comparison bars on his or her homework pages this week. Be sure to check their work. This new strategy is tricky and sometimes our first graders are unsure about where the known information should go. (If the magic number or the difference is known, the information always goes inside the circle.) We will review more comparison stories next week and then we will wrap up Unit 6 with an assessment.