Nrich – Investigations – articles and resources
Number and Algebra Investigation materials
From OCR: Maths investigations OCR
From Teachit Maths, Rich Tasks for KS3-KS4 Maths
On the STEM Learning – Lorraine Mottershead’s book: Investigations.
This resource is the complete book by Lorraine Mottershead; solutions to the puzzles and investigations are included.
Also on the National STEM Centre from David Kirby and Peter Patilla we have Maths Investigations – Pupils’ Workshop together with a comprehensive teachers’ guide.
An old Edexcel document: edexcel-gcse-coursework-tasks-and-projects2540-new-v2