My favourite graphing calculator as regular readers will know is the outstanding Desmos graphing calculator. Preparing some resources for my Further Mathematicians I realised that one can use a slider within a domain thus making it possible to show the curve being traced out, particularly useful for polar graphs but also for any curves. (There are some useful resources on polar curves here for students including some further Desmos pages).
Experimenting with a quadratic graph, I have plotted some points and can then draw the curve through these points.
Have a look at these excellent mathematics resources available from NASA, see this on Scientific notation for example.