Also just to let you guys know, dunno if I've mentioned it before, if you want both Tamara in NCHDL and to have extra activities on Mondays with sisters friend or mum.
1. Get to the part in the Tamara quest-line (follow Tamara) where you beat the guy in the alley, then stop.
2. Get to the part in the Derek quest-line (follow Derek) where Derek and Samantha go on a date, don't go back to see the result (avoid going to the swimming pool area).
3. Tutor Tamara until it triggers the after school events for her (she is now in the NCHDL). Game says you have failed to get one of the people to join the NCHDL and to go see Larson (don't worry you haven't).
4. Wait until end of week, follow Tamara, she will now have joined and NCHDL and be angry (not be able to tutor Tamara for favour anymore). You can get favour other ways as the other school events with her still work.
5. Finish the Derek & Samantha date (go back to swimming pool), Derek will now have joined. Done
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Now you can have Tamara in NCHDL and still have the after school events on Mondays, both paths work in the after school events, so you can either have Mum or sisters friend events, although not both at the same time
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