Kirjalik arvutamine
http://www.thatquiz.org/tq-1/?-jg23-l34-nk-p0
http://www.thatquiz.org/tq-1/?-jg43-l34-nk-p0

Liitmine: http://eu.ixl.com/math/grade-2/add-two-two-digit-numbers-with-regrouping
Lahutamine: http://eu.ixl.com/math/grade-2/subtract-two-two-digit-numbers-with-regrouping