The number 1 is signed by holding up your dominant hand in a fist, facing towards you, with your index finger sticking out.
Don't confuse the number 1 for the letter I, where you stick out your pinkie finger from your fist, facing out.
Teach your toddler the number 1 sign when it is time for them to learn about basic numbers in school, or when they show curiosity about counting objects, money, etc.
This is a useful flash card taught best in conjunction with the other basic numbers.
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