Add 10, 100 or 1,000 to a number
  Add up to 2-digit numbers
  Add up to 3-digit numbers
  Add up to 4-digit numbers
  Add up to 5-digit numbers
  Add lists with up to four-digit numbers

  Add decimals with up to one decimal place
  Add decimals with up to two decimal places
  Add decimals with up to three decimal places
  

  Add proper fractions with same denominators
  Add proper fractions with different multiples of a denominator
  Add improper fractions with same denominators
  Add improper fractions with different multiples of a denominator