i completed my physics ISA last year, the topic was on factors affecting the extension of a rubber band, with the context being luggage cords used on suitcases. but this changes every year, so i wouldn't focus on this topic too much.
you can't really 'revise', as such. you just need to make sure you're 100% clear on all the key terms that will come up in EVERY paper, trust me. here are the main ones you need to learn, so memorise them carefully! (i've taken the definitions from a GCSE revision guide, so they're accurate):
accurate = an accurate measurement is one that is close to the true value
random error = readings are different to true value, they may be compensated by taking a large number of readings
systematic error = cause readings to be spread around true value by using a wrongly calibrated instrument
zero error = caused by measuring instruments that have a false zero
fair test = only the independent variable has been allowed to influence the dependent variable
precision = determined by number of scale divisions on measuring instrument
reliability = results are considered reliable if tests can be repeated and a similar pattern is shown
then you'll also need to learn the different types of variables, e.g. categoric, continuous, discrete etc. etc.
and make sure you've memorised the method you'll need to carry out the experiment, because in your paper there'll be a 9 mark question asking you to explain your method, equipment needed, variables, and risk factor (what is dangerous, how can risks be reduced?)
good luck!