Which One Doesn’t Belong?

 

Shared by Javier Pérez:

This activity is inspired by the Odd One Out that Harriet showed. 

It is well-known in mathematical reasoning.

Which One Doesn’t Belong?

 

Why?

This activity is designed to improve writing and speaking skills in the students.

It is engaging and adapts to all units/topics/lessons/classes, no matter the subject or level.

 

When?

Both at the beginning and at the end of a lesson/topic . It can be used in different ways:

* At the beginning: Students often notice properties they don't know names for. We can introduce new vocabulary.

* At the end: Consolidate new vocabulary/concepts.

 

How?

The students need the time and space to do their best thinking. 

No hands raised; no talking; no pressure for about a minute before. The write in their notebooks the one that doesn't belong and a reason. 

Once they have finished, they test their ideas with a neighbour before sharing with the large group.

Each object in a Which One Doesn't Belong? set has at least one reason not to belong, there is not one right answer. Sometimes they find a reason that is not in your mind. That is very enrichin for both students and teacher.

The different sets can be graded, sequencing them so that they build on each other and rely on more subtle differences.

Furthermore, the students can create their own sets to share/challege their own classmates. 

By doing that they use all the conceptsin the lesson, reinforce the new vocabulary and properties of the objects and are able to create a task involving significant knowledge.

  

Examples (1-2-3-4, left to right, top to bottom)

Functions

1. It is the only one that is a parabola.

2. It is the only one that is not a function.

3. It is the only one with positive domain

4. It is the only funcion crossing the x-axis.

Natural Numbers

1. It is the only one with one digit.

2. It is the only one with a 6.

3. It is the only one with a 5.

4. It is the only that is not a a square number.

Probability

1. It is the only one in which each color has the same probability to come out.

2. It is the only one with only three possible outcomes.

3. It is the only one in which purple has the smallest probability to come out.

4. It is the only that in which blue has the smallest probability to come out.

Rational Numbers

1. It is the only one with two consecutive numbers in numerator and denominator.

2. It is the only one that is an improper fraction.

3. It is the only one not simplified.

4. It is the only one with a 5 in the denominator.