Design / Teach MS Access that has dynamic changable formulas

I have a database I have designed so far, which is essentially a Laboratory database which lets users enter new tests, which consist of various analytes. The user can group all these analytes into a test, and through a client window they can enter new samples, and pick the tests each sample will have (may be multiple) then in the results page I need help, what I want to be able to happen is for a table to be generated that allows for the results to be entered based on the test that was selected. In addition to this, in the Sample table, I have a field called parentsample, which allows a child sample to be generated to a parent sample. I would like to get some help to be able to show all calculations of child samples, as a report below the parent sample. The Main part through, is allowing the database to have the ability to get a user to enter a query in the test, which will be able to be changed for each different test regardless of how many tests there are. What I mean by that is that say for example i have test A, which consists of Time, Weight, Analyte Result, and Surface area. In each test, I enter the forumula and whenever the report is generated, it checks the test to see the query, runs the query which fetches all the individual results, and performs that report. The important this is that one test might do that, but another test might have just Volatile Content, Moisture, Time, Temperature and would need to preform a different calculation on different data which is all contained within the one table (results which contains ResultID, SampleID, Test Name, Test Result, Test Units ) The trick is to allow users to enter it in the test settings table, instead of having to recreate the table each time again and again which is just not really practical. For example the main test might have a parent product, which has surface area, and child products that contain results, air flow, and units, so it would also need to be able to query child and parent samples to find the appropiate value, but this would normally be a set value, i.e it always happens that there are four child products which need to query the pearent products surface area. Need help!, Table is half designed but need help with low budget to work out the other part with modifiable calculations etc.