For K-3 students, perhaps it is not acceptable to introduce multiplication by zero as a property or definition. Instead, the child may think about multiplication as, e.g., repeated addition.
Examples of the "repeated addition" conception: $3 × 2 = 3 + 3 $ and $ 4×3 = 4 + 4 +4$.
My questions:
How will students conceive of $ 3 × 0 $?
How should early elementary/primary curricula deal with multiplication by zero?