Here is a lesson plan on the Latin word roots deca, dec, deka, and deci. The first three mean ten, but deci means tenth. As you have probably already inferred, especially you math teachers, this is a very productive root in English, and will lead students to understand a wide variety of words for transfer across the curriculum. I open this lesson with this context clues worksheet on the noun cipher. This word root worksheet is the mainstay of this lesson.
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