The Add Up strategy will involve adding up in the amount currently being subtracted (subtrahend) to the whole (minuend). Get started by selecting challenges the place the minuend and subtrahend are close collectively (e.g. fifty seven - fifty three or 332 - 326) to build an knowledge of subtraction as https://www.generationgenius.com/videolessons/strategies-to-add-subtract-within-20-make-a-10-doubles-facts/