Odds and Ends of Odds and Evens: An Inquiry Into Students' Understanding of Even and Odd Numbers

Differences in preservice elementary school teachers' perceptions between divisibility by two, or 'evenness' and divisibility by another number have been observed. This led to an inquiry into participants' understanding of the parity of the whole numbers. The results reveal that the equivalence of the number properties of being 'even' and being 'divisible by two' is not taken for granted. Rather, the parity is often perceived as a function of the last digit of the number. The extent of this perception is investigated. Some pedagogical approaches are considered.