does zero have any implications for instruction?
Yes, as the definition of "even" as "integer multiple of 2" is not always appropriate.
Parity of zero
 One issue concerns the foundations of the proof; the definition of "even" as "integer multiple of 2" is not always appropriate. 
what is the parity of zero? The quality of an integer being even or odd—is even. who invented the number zero? Indian mathematician Brahmagupta is this number an even or odd number? Even number what is the main reason for it being an even number? Zero is an integer multiple of 2, namely so zero is even. during which year was the mathematician born? 598 CE where was he born? Bhillamāla, Gurjaradesa apart from math, what else interested him? Astronomy what observations did he make ? That the Moon is farther from the Earth than the Sun. what effect has zero on algebraic patterns? In abstract algebra, the even integers form various algebraic structures that require the inclusion of zero.
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Parity of zero [SEP] Implications for instruction
Mathematically, proving that zero is even is a simple matter of applying a definition, but more explanation is needed in the context of education. One issue concerns the foundations of the proof; the definition of "even" as "integer multiple of 2" is not always appropriate. A student in the first years of primary education may not yet have learned what "integer" or "multiple" means, much less how to multiply with 0. Additionally, stating a definition of parity for all integers can seem like an arbitrary conceptual shortcut if the only even numbers investigated so far have been positive. It can help to acknowledge that as the number concept is extended from positive integers to include zero and negative integers, number properties such as parity are also extended in a nontrivial way.