Gary in CA

The TA work grows much easier the 3rd, 4th, 5th time you deal with the same stuff.  Seriously, you didn't accomplish any research?  That isn't a good reason to move you to RA.  It will be tough for the boss to take you off the U's payroll and put you on his with no track record in the lab.  So I'm not going to recommend you engage in any conversation about the transition.  Teach for a couple of years and get good at juggling everything at the same time, teaching, research, coursework, and reading (plus cumes? seminars? orals? group meetings?).  The PI will see how much you've done and move you on his own schedule.
 
I've got to ask a hard question.  How many hours are you working?

I had a Turkish Princess whose English was limited who refused to wash her lab glassware.  About the only time she tried, she put a nitric acid reaction mixture into the alcoholic KOH bath and blew brown gunk up the wall, across the windows, and all over a 14 foot ceiling.  Then I had a Greek post-doc who refused to dispose of her toxic waste.  She ran everything down the sink with hot water and gassed the lab with pentachlorocyclopentadiene adducts, about like breathing Chlordane.  My solution, using the Cypress model was to lock the Turk and the Greek in the same room and let them kill each other.
 
Seriously?  Work nights.

OP, here's one of my more memorable confrontations:
 
Student comes into my lab where I'm working (distant cousin of the Saudi royal family), "I must have regrade!"
Me, "If I have to regrade one question, I regrade them all.  You will leave with 2 points less than when you entered."
Student (Striking a partial pose), "I know karate."
Me, (picking up a wrench I used to attach regulators to gas cylinders in the chem lab), "I know Crescent wrench." (( In perfect hindsight, I'd never say or do this now. ))
Student leaves.  A few minutes later, loud voice from down the hall (another TA's lab),"I must have regrade!"
 
It takes two to tango.  Withering into the truth of age, I'd do many things differently today.

I had a Turkish Princess whose English was limited who refused to wash her lab glassware.  About the only time she tried, she put a nitric acid reaction mixture into the alcoholic KOH bath and blew brown gunk up the wall, across the windows, and all over a 14 foot ceiling.  Then I had a Greek post-doc who refused to dispose of her toxic waste.  She ran everything down the sink with hot water and gassed the lab with pentachlorocyclopentadiene adducts, about like breathing Chlordane.  My solution, using the Cypress model was to lock the Turk and the Greek in the same room and let them kill each other.
 
Seriously?  Work nights.

OP, here's one of my more memorable confrontations:
 
Student comes into my lab where I'm working (distant cousin of the Saudi royal family), "I must have regrade!"
Me, "If I have to regrade one question, I regrade them all.  You will leave with 2 points less than when you entered."
Student (Striking a partial pose), "I know karate."
Me, (picking up a wrench I used to attach regulators to gas cylinders in the chem lab), "I know Crescent wrench." (( In perfect hindsight, I'd never say or do this now. ))
Student leaves.  A few minutes later, loud voice from down the hall (another TA's lab),"I must have regrade!"
 
It takes two to tango.  Withering into the truth of age, I'd do many things differently today.

Necroposting on something from 3 months ago.  I apologize in advance for being late, losing my wallet, running out of gas.
 
I hate email. Seriously.
 
Try this.  Act stupid.  Take the blame.  Tell them both.  Go to both meetings for a while.  Decide which group later.  Stall.
 
If you're about to make a decision which is going affect the next 5,7,whatever years of your life, it behooves one to do it wisely.
 
As an old man, I've learned to blame Alzheimer's or that motorcycle accident back in '70 when it's necessary.  I sure wouldn't base some life changing decision on a misunderstood email.

Necroposting on something from 3 months ago.  I apologize in advance for being late, losing my wallet, running out of gas.
 
I hate email. Seriously.
 
Try this.  Act stupid.  Take the blame.  Tell them both.  Go to both meetings for a while.  Decide which group later.  Stall.
 
If you're about to make a decision which is going affect the next 5,7,whatever years of your life, it behooves one to do it wisely.
 
As an old man, I've learned to blame Alzheimer's or that motorcycle accident back in '70 when it's necessary.  I sure wouldn't base some life changing decision on a misunderstood email.

ModFuzzyL, You asked good questions and the suggestion to manage expectations is a good one also. But you didn't convince me to promote someone who hasn't yet accomplished anything.  I offer you tea and the opportunity to return and state your case at a later date.
 
Still trying to get to the OP's timecard, 5 one-hour sections and 20 hours of grading doesn't fill the week.  Add in the office hours, cume prep, coursework, homework, group meetings, lit review, a lunch and dinner break and see if you can get to 60? 80?  Kudos if you can do grad school on less.  Internalizing, I never could.  I ended up in the grad lounge for a two-hour dog nap about twice a week and never took weekends off.  Holidays and summers were double-time in the lab as well.
 
Is anyone managing to work less than 80 hours?  If so, I tip my hat.
 
"How many hours per week are you actively working??" would make a good poll question in the "expectations" department.

OP, here's one of my more memorable confrontations:
 
Student comes into my lab where I'm working (distant cousin of the Saudi royal family), "I must have regrade!"
Me, "If I have to regrade one question, I regrade them all.  You will leave with 2 points less than when you entered."
Student (Striking a partial pose), "I know karate."
Me, (picking up a wrench I used to attach regulators to gas cylinders in the chem lab), "I know Crescent wrench." (( In perfect hindsight, I'd never say or do this now. ))
Student leaves.  A few minutes later, loud voice from down the hall (another TA's lab),"I must have regrade!"
 
It takes two to tango.  Withering into the truth of age, I'd do many things differently today.

Necroposting on something from 3 months ago.  I apologize in advance for being late, losing my wallet, running out of gas.
 
I hate email. Seriously.
 
Try this.  Act stupid.  Take the blame.  Tell them both.  Go to both meetings for a while.  Decide which group later.  Stall.
 
If you're about to make a decision which is going affect the next 5,7,whatever years of your life, it behooves one to do it wisely.
 
As an old man, I've learned to blame Alzheimer's or that motorcycle accident back in '70 when it's necessary.  I sure wouldn't base some life changing decision on a misunderstood email.

I had a Turkish Princess whose English was limited who refused to wash her lab glassware.  About the only time she tried, she put a nitric acid reaction mixture into the alcoholic KOH bath and blew brown gunk up the wall, across the windows, and all over a 14 foot ceiling.  Then I had a Greek post-doc who refused to dispose of her toxic waste.  She ran everything down the sink with hot water and gassed the lab with pentachlorocyclopentadiene adducts, about like breathing Chlordane.  My solution, using the Cypress model was to lock the Turk and the Greek in the same room and let them kill each other.
 
Seriously?  Work nights.

Necroposting on something from 3 months ago.  I apologize in advance for being late, losing my wallet, running out of gas.
 
I hate email. Seriously.
 
Try this.  Act stupid.  Take the blame.  Tell them both.  Go to both meetings for a while.  Decide which group later.  Stall.
 
If you're about to make a decision which is going affect the next 5,7,whatever years of your life, it behooves one to do it wisely.
 
As an old man, I've learned to blame Alzheimer's or that motorcycle accident back in '70 when it's necessary.  I sure wouldn't base some life changing decision on a misunderstood email.

ModFuzzyL, You asked good questions and the suggestion to manage expectations is a good one also. But you didn't convince me to promote someone who hasn't yet accomplished anything.  I offer you tea and the opportunity to return and state your case at a later date.
 
Still trying to get to the OP's timecard, 5 one-hour sections and 20 hours of grading doesn't fill the week.  Add in the office hours, cume prep, coursework, homework, group meetings, lit review, a lunch and dinner break and see if you can get to 60? 80?  Kudos if you can do grad school on less.  Internalizing, I never could.  I ended up in the grad lounge for a two-hour dog nap about twice a week and never took weekends off.  Holidays and summers were double-time in the lab as well.
 
Is anyone managing to work less than 80 hours?  If so, I tip my hat.
 
"How many hours per week are you actively working??" would make a good poll question in the "expectations" department.

You've backed into a tough spot, but I'd never recommend removing a member.  You hit on a few of the reasons already.   Was that the question?
 
We have all met people who are so prickly and difficult that no one wants to handle them. Some situations are inescapable. Far better and much easier to begin to develop skills in practical psychology, alter a communication style to fit the situation, and modify the body language.   Managing human resources is more than half the job in every career.

3 months later - This lab is empty too.
 
That's irony. • a state of affairs or an event that seems deliberately contrary to what one expects and is often amusing as a result
swap out amusing for sad or tragic
 
Hang in there.

Necroposting on something from 3 months ago.  I apologize in advance for being late, losing my wallet, running out of gas.
 
I hate email. Seriously.
 
Try this.  Act stupid.  Take the blame.  Tell them both.  Go to both meetings for a while.  Decide which group later.  Stall.
 
If you're about to make a decision which is going affect the next 5,7,whatever years of your life, it behooves one to do it wisely.
 
As an old man, I've learned to blame Alzheimer's or that motorcycle accident back in '70 when it's necessary.  I sure wouldn't base some life changing decision on a misunderstood email.

ModFuzzyL, You asked good questions and the suggestion to manage expectations is a good one also. But you didn't convince me to promote someone who hasn't yet accomplished anything.  I offer you tea and the opportunity to return and state your case at a later date.
 
Still trying to get to the OP's timecard, 5 one-hour sections and 20 hours of grading doesn't fill the week.  Add in the office hours, cume prep, coursework, homework, group meetings, lit review, a lunch and dinner break and see if you can get to 60? 80?  Kudos if you can do grad school on less.  Internalizing, I never could.  I ended up in the grad lounge for a two-hour dog nap about twice a week and never took weekends off.  Holidays and summers were double-time in the lab as well.
 
Is anyone managing to work less than 80 hours?  If so, I tip my hat.
 
"How many hours per week are you actively working??" would make a good poll question in the "expectations" department.

ModFuzzyL, You asked good questions and the suggestion to manage expectations is a good one also. But you didn't convince me to promote someone who hasn't yet accomplished anything.  I offer you tea and the opportunity to return and state your case at a later date.
 
Still trying to get to the OP's timecard, 5 one-hour sections and 20 hours of grading doesn't fill the week.  Add in the office hours, cume prep, coursework, homework, group meetings, lit review, a lunch and dinner break and see if you can get to 60? 80?  Kudos if you can do grad school on less.  Internalizing, I never could.  I ended up in the grad lounge for a two-hour dog nap about twice a week and never took weekends off.  Holidays and summers were double-time in the lab as well.
 
Is anyone managing to work less than 80 hours?  If so, I tip my hat.
 
"How many hours per week are you actively working??" would make a good poll question in the "expectations" department.

You've backed into a tough spot, but I'd never recommend removing a member.  You hit on a few of the reasons already.   Was that the question?
 
We have all met people who are so prickly and difficult that no one wants to handle them. Some situations are inescapable. Far better and much easier to begin to develop skills in practical psychology, alter a communication style to fit the situation, and modify the body language.   Managing human resources is more than half the job in every career.

OP, here's one of my more memorable confrontations:
 
Student comes into my lab where I'm working (distant cousin of the Saudi royal family), "I must have regrade!"
Me, "If I have to regrade one question, I regrade them all.  You will leave with 2 points less than when you entered."
Student (Striking a partial pose), "I know karate."
Me, (picking up a wrench I used to attach regulators to gas cylinders in the chem lab), "I know Crescent wrench." (( In perfect hindsight, I'd never say or do this now. ))
Student leaves.  A few minutes later, loud voice from down the hall (another TA's lab),"I must have regrade!"
 
It takes two to tango.  Withering into the truth of age, I'd do many things differently today.

Kick out the pre-meds; that should solve your problems.
But if you can't do that... Hm. The games and fictional stuff are what I would have tried. I was reminded of the game I made up for a biology friend's baby shower, where we had to match the name of the baby animal to the name of the species, but the species names were in Latin. (So we had to match the faun with the Odocoileus virginianus ... which was funny once you know it, b/c white tail seems to translate as virgin anus... but I digress.) What was interesting was that next to the mother-to-be, our astronomy friend did the best because so many of the names correspond to constellations/astronomy signs.
But if the students are acting "too cool for school" it's hard to say. When I would teach after school classes for kids, there would be a few whose parents made them sign up, and they were bound and determined to be unhappy just to prove their parents wrong; it seems like these college kids are doing the same thing.
How are they performing in class? Maybe you can channel their desire not to participate? I had a math teacher who would give us a quiz over stuff we hadn't done in class yet. If we got 100%, we didn't need to do the homework that night. Could you give them quizzes that aren't for grades, but are for a get-out-of-class free period? Like, if on Monday they can prove they already know the stuff you'll be working on all week, and if they don't care about extra credit and such, then they can skip class without any penalties or hard feelings. Maybe if they felt they had a choice, then they wouldn't feel so bound and determined to prove to you that they didn't want to be there.
Alternatively: Jolly Ranchers. There's a whole book called "Punished by Rewards" about how you shouldn't incentivize learning with gimmicks, but I'm okay with it. One time at work someone organized a "Throw Back" lunch where we brought in all the classics from our childhoods in the 90s (Gushers fruit snacks, PB & Js, Lunchables, Capri Suns, fruit by the foot, etc.) and then played a game of Heads-Up-Seven-Up. We had officially allowed ourselves to be kids, so nobody was acting too cool to play along. If your students are trying to establish that they're too grown-up for games, maybe you can go all out into throw-back mode, have a time warp to 6th grade and winning Jolly Ranchers, and call it good.
Sounds like a frustrating situation, especially since you know that what you're trying has worked before. Good luck!