# Investigations Blog

## Q&A: The Order of the Units

Question: Can the Investigations units be taught in a different order than suggested?Answer: The first edition of Investigations was written as a “replacement unit” model where individual units within a grade were somewhat less dependent on previous units, and schools and districts often chose their own sequence, or decided to teach only 3 or 4 units the first year of implementation. That was the 1990s! The units in the 2nd and 3rd editions were written as a complete, coherent, full-year...

read more## A Grade 3 Q&A: Why start with multiplication and division?

Question: Why does 3rd grade start with a multiplication/division unit and not addition/subtraction?Answer: We often hear from people who wonder why Grade 3 starts with a multiplication and division unit—just like it did in the 1st edition!—rather than an addition and subtraction unit. As we decided on the sequence of the units in any grade, we considered many different things. The most important was the development of mathematical content within and across grades.In Investigations 3,...

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