Linear functions and graphs

problem
Intersections

Age

14 to 18

Challenge level

Change one equation in this pair of simultaneous equations very slightly and there is a big change in the solution. Why?
problem
Reflect again

Age

16 to 18

Challenge level

Follow hints to investigate the matrix which gives a reflection of the plane in the line y=tanx. Show that the combination of two reflections in intersecting lines is a rotation.
problem
Enclosing squares

Age

11 to 14

Challenge level

Can you find sets of sloping lines that enclose a square?
problem
On the road

Age

14 to 16

Challenge level

Four vehicles travelled on a road. What can you deduce from the times that they met?
article
Spaces for exploration

Alf Coles writes about how he tries to create 'spaces for exploration' for the students in his classrooms.
article
Coordinating classroom coordinates

This article describes a practical approach to enhance the teaching and learning of coordinates.
game
Favourite

Diamond collector

Age

11 to 16

Challenge level

Collect as many diamonds as you can by drawing three straight lines.