Show that you can use mental math strategies and number properties to add and subtract numbers with answers to 18...

Alien AdditionMinus MissionFun 4 the Brain

Number Line

by using doubles and near doubles

Dinosaur Dentist
by making 10

Math Lines 10Math Lines 20

by using the commutative property

Number Balance
by using the property of zero

by thinking addition for subtraction

Number Line Bounce