SPELLING words + VOCABULARY * Math & Science words Master the spelling and definition of the following words: 1. multiplication – A math operation involving combining equal groups together. 2. product – The answer to a multiplication problem. 3. division – A math operation involving splitting a quantity into equal groups. 4. quotient – The answer to a division problem. 5. thousand – Equal to ten hundred (100 added ten times!). 6. earth – The planet we live on. 7. layer – A single thickness of something. 8. mantle – The middle and largest layer of earth, make of hard rock and liquid rock. 9. core – The center layer of earth with two parts: inner core and outer core. Outer core is liquid rock; the inner core is thought to be a solid ball of iron and other minerals. 10. crust – The top layer of earth, made of rocks and soil. We live on the crust.