Scientific notation that's involved with numbers less than one, should always be counted from left to right. Count starting from the decimal until the first number you "jump over". What are you counting exactly?- the number of digits between the decimal and the first 'number' other than zero.
0.0000321 can be also written as 3.21*10^-5 (or 10 with a negative 5 exponent)
Hope this helps.