To stop MR WACKER expelling ERIC after 10000 lines:

POKE 63931,201

To prevent teachers from giving lines to ERIC or anyone else:

POKE 30464,201

However, that won't prevent MR WACKER from giving ERIC 2000 lines during the 'special' playtimes (if EINSTEIN tells WACKER what ERIC's up to, or WACKER finds the pea-shooter on the fire escape). For that you need:

POKE 63468,0

One harmless side-effect of this POKE is that the lines total will be printed as '00' instead of '0' when WACKER delivers his 'TAKE 2000 LINES...' speech.

If 'Infinite lines' or 'No lines' makes things too easy, use a selection of these POKEs that disable lines-giving for specific infractions:

CATAPULTS ARE FORBIDDEN - POKE 62545,195

DON'T HIT YOUR MATES - POKE 62661,195

DON'T SIT ON THE STAIRS - POKE 30698,24

DON'T TOUCH BLACKBOARDS - POKE 62366,1

GET OFF THE FLOOR - POKE 30758,201

GET TO WHERE YOU SHOULD BE/COME ALONG WITH ME BOY/HURRY UP YOU HORROR/DON'T TRY MY PATIENCE BOY - POKE 30736,0

NEVER BE LATE AGAIN/AND STAY THIS TIME - POKE 62249,1

NOW DON'T DO IT AGAIN - POKE 27196,201 (after a teacher has been knocked over)

NOW DON'T DO IT AGAIN - POKE 62294,1 (when EINSTEIN says 'ERIC hit me')

NOW FIND A SEAT - POKE 30749,201

THE ROOM IS PRIVATE - POKE 30717,31 (also suppresses GET TO WHERE YOU SHOULD BE if ERIC is in the head's study or the staff room when he should be in class)

YOU ARE NOT A KANGAROO - POKE 62780,99

To change the lines limit from 10000 to 10N:

To change the expulsion message MR WACKER delivers (at F1E6) accordingly, you will need to POKE the ASCII codes of the digits of the new lines limit into addresses F1F4-F1F8.

For example, to change the lines limit to 20000 and adjust the expulsion message to match:

POKE 63935,7: POKE 63943,208: POKE 61940,50

To make sure that EINSTEIN never tells tales:

POKE 62270,24: POKE 62321,24

Alternatively, to make the teacher always give lines to EINSTEIN for telling tales:

POKE 31982,0

Hitting all 15 shields before obtaining the safe combination, and then hitting all 15 shields again after opening the safe can be hard work for a busy skoolboy. To reduce ERIC's task to hitting just one shield (any shield):

POKE 63673,1

Note that in order to go up a year, ERIC will have to hit the same shield as he hit before opening the safe.

Having to knock down the teachers (or, in CREAK's case, discover his year of birth and then write it on the blackboard in the classroom he'll be teaching in next) in order to obtain the safe combination letters, and then try up to six permutations of those letters before hitting the right one, can be a tiresome task. How much easier it would be if BOY WANDER and the teachers took it upon themselves to reveal the safe combination every time they wrote on a blackboard:

The teachers and BOY WANDER will actually write the safe combination followed by WACKER's, ROCKITT's, WITHIT's and CREAK's individual safe combination letters, in that order, but those last four letters can be ignored.

Normally the lesson clock (at 7FF7) counts down from 5376 (21*256) to 0, at which point the bell rings. To make the lesson clock count down from N*256 to 0 instead:

POKE 26344,N

If you are extending the lesson length, it's a good idea to also adjust the time at which teachers will tell the kids to sit down. Normally this is 3840 (15*256); to change it to M*256 (M=N-6 is a good choice):

POKE 31811,M

If, on the other hand, you are shortening the lesson, it's a good idea to also adjust the time at which teachers will start giving lines to ERIC for being in the wrong classroom. Normally this is 4864 (19*256); to change it to G*256 (G=N-2 is a good choice):

POKE 30771,G

To put ERIC in charge of ringing the bell:

Now whenever 'L' (upper case) is pressed, the bell will ring and the next lesson will begin (which could prove handy if ERIC is found playing truant, cannot be bothered to hide from ANGELFACE when he has mumps, or simply cannot wait any longer for playtime).

Normally 'q', 'a', 'o' and 'p' make ERIC walk, and 'Q', 'A', 'O' and 'P' make him run. To make ERIC always run, regardless of whether SHIFT is held down:

POKE 25941,24

Or, to make ERIC walk when SHIFT is held down and run when it isn't:

POKE 25941,32

To extend the range of the catapult from 13 to N:

POKE 28773,N

However, this doesn't extend the 'hit zone' of the pellet (the portion of its flight where it can hit something). To change the hit zone from the last 7 stages of its flight to the last M stages (M=N-6 is a good choice):

POKE 28000,M+1

To enable ERIC to walk through specific walls: