In this feature students are invited to explore a variety of problems and are then challenged to construct convincing arguments to explain what they have discovered. They offer an opportunity for rich mathematical discussion in the classroom.
The last day for students to send in solutions to the live problems is Monday 16 May.
Plus magazine has a selection of interesting articles looking at logic, the basics of mathematical logic, its role in computer science and the philosophy of maths, and on how it's being used in applications.
You can watch a recording of the webinar in which we discussed the mathematical thinking which can be prompted by these activities.
River crossing
Isosceles seven
Is it possible to find the angles in this rather special isosceles triangle?
Iffy logic
The Tour de Clochemerle
Can you work out where these 5 riders came in a not-quite-so-famous bike race?
Iff
Mind your Ps and Qs
Sort these mathematical propositions into a series of 8 correct statements.