Which One Doesn't Belong? is a structure where students answer this question given four mathematical objects (shapes, numbers, graphs, etc.). There are many different correct answers and justifications for choosing which one doesn't belong. In fact, there is a justification for each of the four objects!

You can use this in a Four Corners activity or as a Number Talk style prompt to get students thinking and reasoning. You can even ask students to make their own WODB.

• Which One Doesn't Belong website

• Which One Doesn't Belong book for children

• Video of how to use WODB with your students

PD via Twitter: @WODBMath, @marybourassa, @Trianglemancsd, #wodb

Same or Different can be used within a Number Talk where students have time to think, then share characteristics with a partner, small group, or the class. The teacher moves the conversation along and prompts students to fully explain their thinking, and make connections.

• Video of this routine in action in a Kindergarten class

• Same or Different images (K-11)

• Same or Different Videos (1-5)

• Same But Different Math images (K-10)

PD via Twitter: #samediffmath

Would You Rather? is a comparison routine where students choose a path and justify it. This is a strategy that helps to build students' ability to use their intuition and estimation skills, as well as their ability to provide a clear mathematical argument or proof for their choices.

The options are presented as engaging images. For example, the images include food options, subscription plans, rates of time or money, unit conversions, etc.

• Would You Rather Math images (K-12)

PD via Twitter: #WYRmath, @Jstevens009

To play Attribute Train, you need a bunch of stuff -- can be math manipulatives, items you find around the class, or even images mixed up on a smartboard (of random objects, math manips, graphs, functions, etc.)

Pick one item. Then, students look at the rest of the objects, and select one that has something in common with the first, and place it in the line. They explain the commonality and continue building the train in this fashion.

Once finished, consider going back and asking students to review the characteristics that were in common between each pair of items.

• Attribute Train explained for young children

Desmos Polygraph activities allow students to ask each other questions based on groups of characteristics to identify the mathematical object their partner has selected. Polygraph is similar to the board game "Guess Who?"

Desmos Polygraph allows students to transfer their informal language to formal mathematical vocabulary when discussing the attributes of Shapes, Angles, Translations, Functions, Domain and Range, and more.

The teacher dashboard allows the teacher to view and snapshot the questions students are asking to draw attention to key questions and help consolidate the learning after the actvitiy.

To make your own Desmos Polygraph, sign in, click Custom, and then select "New Polygraph" at the top right corner.

• Polygraphs Made by Desmos

• Polygraphs Made by Others

PD via Twitter: @Desmos