Recently I was in a Grade 6 classroom and the teacher gave this problem to her students to solve.

**Mrs. M is planning on cooking a turkey. She read online that it takes 20 minutes to cook 500 grams of turkey. The turkey weighs 9.75 kilograms. About how long will it take to cook the whole turkey?**

This is a great example of a proportional reasoning problem. Students need to have knowledge of the relationships between grams/kilograms and minutes/hours.

When students work on a problem like this we want them to understand that they can figure out any size turkey based on the time/weight relationship (Big Idea).

On another note: With students I always try to remember to read 9.75 as 9 and 75 hundredths (fractional language) instead of 9 point 75. This helps with building the understanding of the relationship between fractions and decimals – a fragile concept for many!

In the first photo students are demonstrating an understanding of the relationships I mentioned. My feedback: Do you have to fill in the whole chart? At what point could you have made a calculation based on the pattern you have identified? I want them to see that at the 200 minute/5000 grams mark they could have “doubled” both. That’s multiplicative thinking!

In the second photo the students have followed a fairly straightforward procedure for solving this. I chose this particular piece to share because of the way they have annotated or labeled their numbers in the calculations. This is a strategy that I promote because it encourages students to think about what the numbers represent in the problem and it gets away from elaborate explanations that do not add value to the solution.