Linear or nonlinearLinear or exponential
Does each one grow by adding or by multiplying? Circle linear or exponential.
Does it grow by adding the same amount, or by multiplying by the same amount? That one question separates a linear function from an exponential one, and these free printable worksheets ask it eight times a page, with an answer key.
If they get stuck

The answer key prints on a separate page.
Half the questions are tables and half are short situations. In a table the child compares neighbors: 29, 38, 47, 56 adds 9 each time, so it is linear, and 2, 4, 8, 16 doubles each time, so it is exponential. A table that goes down counts too. 16, 8, 4, 2 halves each time and is exponential, while 16, 11, 6, 1 takes away 5 each time and is linear.
The situations ask the same thing in words, and the words are where it gets harder. A candle that burns 3 cm each hour is linear, and a pond whose lilies triple each week is exponential. The one to watch is a percent: a car that loses 10% of its value each year loses a different amount of money every year, and that is what makes it exponential.
x: 2, 3, 4, 5 y: 16, 11, 6, 1