Relationships & Auto-Filling

HI. New to FM. I'm understanding many of the basics, but not getting some. Here's my dilemma:

I have a table of physical fitness test scores within 6 tests: (mile run, etc...). Each test has a preferred range of scores (a hi-value and a lo-value). These value's change depending on two variables: gender and age of the student. So I wrote a table (I call "Standards") that recorded the age & gender and the corresponding values for them in the various fitness tests.

Now, I create another table ("Students") I create age/gender fields that the user selects from a drop-down list and fields with same names as the hi/lo scores. I made these fields (the fitness scores) as Lookup fields, referring back to the other table (Standards).

Now my problem: when I test this table (Students) in Browse mode, the fields for the hi/lo scores (that refer back to the other table (Standards) do not change, and remain blank when I enter info in the gender and age fields.

I was expecting these to automatically enter the corresponding values from the "Standard" table when I enter an age & gender.

Any suggestions?

--Mark