How to return the number of words in a cell?

Answer: the following formula will return the number of words in an excel cell.

 =If(LEN(TRIM(B1))=0,0,LEN(TRIM(A1))-LEN(SUBSTITUTE(B1," ",""))+1)

Possible situation where you would want to use this formula: I download students data because I'm a DBA at xyc district. One column of data gives me the grades of each school (k 1 2 3 4 5). The next column gives me total enrollment. I want to find the average enrollment in each grade at each school. I would use the above formula to find the number of grades in each school so I could divide enrollment by number of grades at each school.