is there a way to 'unlock' all the training lessons? I have gone through all of them, but everytime there is a update i lose them, and have to do them again?! there has to be a way to open them without playing them again?

No way to my knowledge.
However the training lessons are useful after a new patch because of the changes in the patch, that often affect your driving.
For example the addition of clutch temperature has modified the way you can drive / launch the cars, so it is not too bad that you have to start again.
Furthermore the last lessons are not really good, only AIs overtaking... that you can do in single player with more variety and better setups.

u learn more online that u do in the training sessions tbh.
When i first got LFS and i tryed i failed so i went online.
I attempted them a couple of weeks after some races and finished it in under and hour

you learn more online but you don't learn the same things.
You won't be given the chance to learn good car control when racing online and i am pretty certain most would not consider it really nice to have someone toy around with the controls while the rest want to race.

think of it as something that teaches you the very very basic ablities one needs to start going round a circuit. for you who can race easily it might not seem important but for someone who just now starts with lfs (not talking about the OP, necessarily) they are great help.

Quote from george_tsiros :

you Learn more online But You Don't Learn The Same Things.
You Won't Be Given The Chance To Learn Good Car Control When Racing Online And I Am Pretty Certain Most Would Not Consider It Really Nice To Have Someone Toy Around With The Controls While The Rest Want To Race.

Think Of It As Something That Teaches You The Very Very Basic Ablities One Needs To Start Going Round A Circuit. For You Who Can Race Easily It Might Not Seem Important But For Someone Who Just Now Starts With Lfs (not Talking About The Op, Necessarily) They Are Great Help.

+1