Looking for a quickstart that is also a one shot

I am going to the beech with the family this fall. they have asked me to run D&D. But they have never played D&D and honestly I think the most we will play at the beech is 1-3 four hour sessions.

I see some decent quick starts but most are for groups committed to a longer 5-10 session thing. 

I am looking for recomendations

There are some super tiny things, such as https://www.dndbeyond.com/sources/dnd/bqdd/borderlands-quest-dagger-danger . How much you can actually get through in 1-3 sessions with complete novices is heavily dependent on the group.

I have low expectations of 50% of them lol thanks

Worth taking a look at Peril in Pinebrook. It was released a couple of years ago as a one shot people who play could run at Thanksgiving with their families who had never played. It’s about two hours to run but the best thing is it comes with abbreviated character sheets that are only about half a page and only use a d20 and a d6 so greatly cuts down on the amount of confusing things to give new players 

I would do Heroes Feast Saving the Children’s Menu.

Crank back the level but keep the scenario the same.

Make sure to bring the Mac and cheese or whatever the food item is to the beach.

I'd definitely recommend my one: the Steepfield Cheese Chase (link to this forum).

It's about 8 hours long, full of good D&D combat, and as for whether it can lead to more - I'm prepping session 75 of a 3-year campaign which came off the back of this oneshot!

Pick your path using the Encounter of the Week posts from D&D Beyond.

If you can find it without buying the book, the Golden Vault has some great really quick one-shots. That's where I'd go.

Otherwise, I might suggest not even doing a full storyline or one-shot. If you've only got 1 - 3 hours,  maybe just draw up a quick dungeon dive. Give a bit of story, set an adventure hook, then send them off to clear a dungeon or ancient tomb of monsters. I'd start it at the adventure hook, like in the tavern or thieve's guild or something, so they can get the experience of interacting with the world on top of just fighting monsters. But then I'd just star wipe them to the dungeon entrance.

For a short session, with players who don't know the rules, you probably won't have time to get through more than two or three encounters total, so you can easily doodle up a four room dungeon with a bit of treasure along the way. And if things move quickly, or you play for longer, then you can easily add a few more rooms and monsters as you go. Maybe bullet point up a couple extra story ideas just in case things go well. Like, the first hook is "We are troubled by local goblins that have taken up residence in a nearby tomb, clear them out for us." But you can also have an option for "The goblins have disturbed the dead, which might now rise from their graves to cause even more trouble" and the third is "You find references to a vast treasure buried deeper in the tomb, if you can claim it." 

With 1-3 hours, you probably won't make it past four rooms and two or three fights with goblins. But if they have a great time and want to keep playing, you can sketch out a few more rooms and toss in the new plot hooks as you go.

One other thought, I'd make sure to pre-generate characters for them. Otherwise you'll spend that whole time just pouring over character sheets and builds. Good luck and have fun!

Edit: I didn't mean to imply you shouldn't buy Golden Vault. Honestly, you absolutely should! It's a great set of one-shots. I just meant that it's probably not worth buying a whole book for one three-hour playtest. If you can borrow it from someone or get it from the library or something, that's what I'd do. But if you want a set of one shot heist-themed adventures? Strong recommend.