This PDF can be used on tablets, phones, and computers to practice Addition to 20 math facts. These task cards are completely paperless and are self-correcting. Students will tap the correct answer to the math question. If correct, it will advance to the next task card. If incorrect, they will be directed back to correct their answer. __________________________________________________________________________ For iPad: You will open in iBooks (Books) on your iPad. It can be stored there, too.