What the heck

I started a campaign with a bunch of beginners. To give them an easy start at lvl 1, I gave them a portable hole and a bag of holding. If you had to guess what they did?

A: They never got the stuff

B: They found it and left it because it's cloth and a bag

C: They appreciated their magical gifts

D: They decided to put the cloth in the bag, thinking it was some sort of Legend of Zelda trial, created a tear in the fabric of the universe, all five failed the save to hold on, and 5 level 1 players are now stuck in the astral sea.

Based on your answer,  WHAT THE HECK DO I DO!!!!!!!!!!!!!!!!!!!!!

Have astral sailors pick them up and scarp all your campaign plans. It’s now an adventure through the astral sea in order to find a portal back home, with all the terror and wonder that it brings.

Why would you give them that?  DId you you not tell them the consquences?  To be honest, you should have immedately told them to redo that action of combing them.  But the best is to go back and do a mulligan or have them reroll new charaters.

Have them all roll an Arcana check, and tell whoever got the highest, "...and on a [Highest number], that's what you imagine could happen if you were to combine two items which open into a demiplane."

(Or just let them redo it. I think that even Matt Mercer either forgot about that or didn't track that in Campaign 3 of CR, because I'm pretty sure a PC with a bag of holding entered a portable hole at least once, and nothing happened.)

I think this might fall into knowledge the players wouldn’t know but the characters might since they live in a magical world where this stuff occurs. I agree that an arcana or history check might have been in order, or heck just tell them. 

Now that it’s happened… pretend it was a dream or premonition of what could happen? I mean, getting out isn’t meant to be easy, so you don’t want it to be just a quick detour. At the same time though, it is your game and what you say about reality pretty much goes.

I don't think this is a problem, unless you're really strict about following "official lore" or something.  While the astral plane is canonically a dangerous place that's difficult to return from, you can have literally anything happen to the party.  They could get hurled on a wild and chaotic trajectory through the astral plane and immediately tossed back out, in an unfamiliar place, and now their level 1 adventure is figuring out where they are.  Then they start the journey home, through wild adventures and encounters along the way.

If that sounds doable, then you just had the first arc of the campaign dropped right in your lap, and all you have to do is fill out the details.  

BUT, that may require an amount of world-building and improvisation that you weren't planning to do, or maybe don't have the time for.  If you were planning to use a pre-written module or something then this probably doesn't work.

why did yall assume it was letter D? they all appriciated their gifts and continued playing. I cant beleave you people. Jk thx for the responces. I think i will go with the "And that is what would happen if you combine them." But I may add that they all got eaten by an astral dreadnought or something just for fun

Just make it a spelljammer campaign. Like an above poster said. They get picked up by some gun-toting hippo-people and robot gnome. It will be a very memorable first campaign. 

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