William invites the students to get involved in ten activities which develop problem solving strategies, mental arithmetic, and logical thinking. A level of difficulty ranging from 5 to 100 can be set. In the main menu one or more activities can be selected. The activities to select from are: • the magician conjures sums: find missing operation; • the painter mixes numbers: correlate sums to numbers; • the gardener picks apples: correlate number pairs; • the grocer weighs packages: equate result