Fibonacci numbers are 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, … where the next number is the sum of the previous two numbers (2 = 1+1, 3= 2+1, 5 = 2+3, etc.)
We found Fibonacci numbers in many things in nature (due to growth and efficient packing of parts.) This is a page that lists many interesting things about the numbers and activities that adults and kids can do for fun.