- Building number sense: The number system (Investigations in number, data, and space)
- How Many in All?; Counting and the Number System; Grade Level K (Investigations in Number, Data, and Space)
- Number Games & Story Problems: Addition & Subtraction (Investigations in Number, Data, and Space Series)
- Mathematical thinking at grade 1: Introduction (Investigations in number, data, and space)
- Mathematical Thinking at Grade 5: Introduction & Landmarks in the Number System (Investigations in Number, Data, and Space Series)