In the activities presented, students work in groups of four and receive four cards, each with a different clue about the problem. Without showing their cards to each other, each member reads aloud their clue. The group is also given solving cards or other manipulative materials. There are multiple versions of each type of problem. The activities cover all three strands of the mathematics curriculum with many interesting problems, such as Find the Number, Shapes & Objects and Probability. There are comprehensive notes (with a particular focus on the mathematical vocabulary associated with the topic), and answers are given. There are now five volumes available. The others in the series are: Check the clues A (for Pre-Primary), Check the clues B (for Years 1 and 2), Check the clues C (for Years 3 and 4), Check the clues E (for secondary students).