As far as I can see, if you have the Red Box:
* You can create a 1st level character as a Dwarf, Elf, Halfling or Human... and choose Fighter, Rogue, Wizard or Cleric for your class
* Someone can DM a premade adventure for 1st level characters consisting of 7 encounters, including a skill challenge/negotiation and a trick involving a chessboard. (Yay!)
* The characters can reach 2nd level.
* The DM can create new adventures for 3-5 PCs, with advice for major and minor quests, and from a selection of 34 monsters.
* Treasure rewards are given for a 2nd level adventure. (The intention is that the adventure the DM creates will be 2nd level, I think).
* You get an overview of the Nentir Vale.
* Interesting things: Improvise Skill Check DCs and a Base Overland Speed table!
You can also download a solo adventure for 1st level characters using the code given in the set...
Particularly interesting, on page 39 of the DM book it talks about the importance of getting feedback on the players and finding out what the players liked... and describes them as actors (who liked the roleplaying), slayers (who like combat), explorers (who like learning about the world of the game), Storytellers (narrative), Thinkers (puzzle-solvers) and Instigators (who like to make things happen).
The adventure in the book assumes a group of 1 DM and four players. By some strange coincidence, there are enough pieces in the book for four characters to play if everyone has a different class! There are, alas, no notes for scaling the adventure that I could see.
All in all, you should be able to get 15-20 hours of play out of the Red Box before you really need the rest of the Essentials line. Or you could stay at level 2 and play some more adventures...
Cheers!
* You can create a 1st level character as a Dwarf, Elf, Halfling or Human... and choose Fighter, Rogue, Wizard or Cleric for your class
* Someone can DM a premade adventure for 1st level characters consisting of 7 encounters, including a skill challenge/negotiation and a trick involving a chessboard. (Yay!)
* The characters can reach 2nd level.
* The DM can create new adventures for 3-5 PCs, with advice for major and minor quests, and from a selection of 34 monsters.
* Treasure rewards are given for a 2nd level adventure. (The intention is that the adventure the DM creates will be 2nd level, I think).
* You get an overview of the Nentir Vale.
* Interesting things: Improvise Skill Check DCs and a Base Overland Speed table!
You can also download a solo adventure for 1st level characters using the code given in the set...
Particularly interesting, on page 39 of the DM book it talks about the importance of getting feedback on the players and finding out what the players liked... and describes them as actors (who liked the roleplaying), slayers (who like combat), explorers (who like learning about the world of the game), Storytellers (narrative), Thinkers (puzzle-solvers) and Instigators (who like to make things happen).
The adventure in the book assumes a group of 1 DM and four players. By some strange coincidence, there are enough pieces in the book for four characters to play if everyone has a different class! There are, alas, no notes for scaling the adventure that I could see.

All in all, you should be able to get 15-20 hours of play out of the Red Box before you really need the rest of the Essentials line. Or you could stay at level 2 and play some more adventures...
Cheers!