## Number Properties Puzzle

**Why I like this problem: **This puzzle was a great review of basic math concepts yet challenging enough to keep students attention throughout the entire class period. I also like that it involved manipulating the labels and numbers, making it a different type of activity and engaging for tactile learners.

**Observations from class: **Many students did not know what a triangular number was and had to look it up. I offered them bingo chips and explained that they are numbers that can be shaped into triangles. Some used the chips to find a rule to calculate triangular numbers and others kept adding rows and recording the number of chips they had.

**Follow-up questions I asked: **

1. Why did you choose to put the labels the way you did?

2. Are there any labels that must be in the same sides? What about the opposite sides?

3. Were there any numbers that must be placed at certain label intersections?

4. What knowledge did you use to place or eliminated number placements?

**Required skills / content: **Math vocabulary (factor, multiple, prime number, square and triangular numbers), understanding two-way tables.

**Source: **https://nrich.maths.org/