historical demographics from Census schedules - how to compare? what test to use?

#1
I have 1900 Census schedule sheets for several boarding schools. Ive gone through the trouble of transcribing the schedule sheets into a database, recording age, gender, race and place of birth of the students at each of the school.

I want to compare each of the schools data to a model that I created of what the "ideal student" should have been. Here are some of the criteria for the model scenario for student enrollment at the boarding schools.
1. Equal proportions male and female students
2. Between the age range of 12 to 21.
3. ....
.
.
I have this model student scenario constructed and have defined criteria for each demographic variable. I have also made frequency counts of each variable for each of the the schools. I am wondering what statistical tests are appropriate to compare the expected values in the model to the observed values in the Census?

I've ran across several problems so far. My first roadblock came when I was told by a professor that I am not dealing with a sample data set, but instead I am working with population data. Traditional statistical tests are for samples and not populations, unless I am wrong about that. I am definitely in need of help on what tests I can use on population data (if what I have is actually population data).

The second problem is that I am wanting to compare an expected range of values to the observed census data values. I am not sure how to compare a range, ie, the age range of 12 to 21.

Any and all comments and suggestions are extremely appreciated. I can post example data and can possibly compensate the right person for help working on my data set. Thanks again.