Odd or Even? Write Two Equal Addends

Eight cards fill this 2nd grade page. Each prints a number, an equals sign and three boxes — two of the same size joined by a plus, and a smaller one labelled left over — with an array of dots beneath. The sheet shown works on 17, 3, 18, 12, 8, 13, 14 and 19, and the dots are laid out in rows of ten so they can be ringed two at a time. The child circles the dots in pairs, writes the number as two equal parts, and puts what is left in the small box.

This is the standard's own definition rather than a rule of thumb: an even number is one that can be written as a sum of two equal addends, and the small box is where an odd number admits that it cannot. Writing 17 as 8 plus 8 plus 1 keeps the structure visible instead of hiding it in the word odd, and four of the eight numbers are even so the left-over box is filled with nothing half the time.

One sheet, eight numbers, twenty-four boxes. The dot arrays do the work for a child who is not yet fluent, so a pencil and a lot of small circles is the intended method, not mental arithmetic. Print it after the odd-house page, where the same pairing was shown rather than done, and before the ones-box page, which drops the dots entirely.