How to make an observation table and which takes input from users and finally makes a 2-D graph?

I am making a physics Lab experiments simulation. For example: The user will drop a ball from different heights several times and note the time taken for each drop. So I wish to create a table in which the user can input the "heights" and "times" and finally show the relation graphically. In short make a table taking variables X and Y many times and producing the X vs Y plot. Thanks