Odd One Out starters
These starter grids are designed so that several options can be defended. Ask students to choose one, explain the rule they are using and then look for a different possible answer.
They work well as projected do-now tasks, discussion prompts or quick routines for mathematical vocabulary and justification.
Visual maths
Which one does not belong? Look for more than one answer before discussing.
A could be different because it is not square.
B could be different because it is shaded.
C could be different because it has been rotated.
D could be different because it has five sides.
Number sense
Which number does not belong? Try properties, factors, digits, parity and square numbers.
72 could be different because it is not a square number.
49 could be different because it is odd.
64 could be different because it is a cube as well as a square.
36 could be different because its digits add to 9.
Algebra
Which graph does not belong? Consider shape, gradient, turning points and rate of change.
B could be different because it is curved and has a turning point.
C could be different because its gradient is zero.
D could be different because it has negative gradient.
A could be different because it is the only increasing straight line.
Reasoning
Which object does not belong? Think about use, shape, material, time and whether it opens something.
A could be different because it measures time.
B could be different because it is normally used for drinking.
C could be different because it contains written information.
D could be different because it is used to unlock something.
