I'm not going to go into which schools to use as that has been done to death elswhere. I'm distance learning alongside a full time job, as well as a 3 month old baby and having just finished a part time MSc with my employer all at the same time - so it is possible! I generally do not have any hard and fast work / revision times as the 3 month old has his own timetable which he makes up as he goes along .
, so I generally cannot schedule time to sit down and work. I bring reading material and printed out feedback questions to work do do at lunchtime and try and do something, no matter how little, every night which keeps the momentum going.
I'm doing mine with london met and they split it into 3 modules - which makes it a bit more manageable - also the modules are related - i've just take the PoF, performance and Airframes / Systems exams. Doing Performance and Pof together was good as they are so closely related. 2nd module is all the nav and comms subjects which I am just starting.
I don't think any of it is particularly difficult - there is just alot of it. Bottom line is you will find the time and motivation if it is important enough to you - which I guess is the whole point of the exams!