Is Nancy a sophomore in season 1?

• The teenagers and young adults starring on Netflix's "Stranger Things" are starting to age past their characters in the show. 
• Eleven, Mike, and the other kids are supposed to be heading into freshman year of high school in season three of "Stranger Things."
• Millie Bobby Brown, Finn Wolfhard, and their costars range in age from 14 to 19 years old.
• Joe Keery, 28, has the biggest age gap with his character, Steve Harrington, who is 18 in "Stranger Things."
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The young stars of Netflix's hit series "Stranger Things" are starting to age past their fictional counterparts on the show. Both Sadie Sink (who plays Max) and Caleb McLaughlin, for example, are 19 years old while their characters are meant to be about 14 and just starting high school.

Keep reading to see how each of the teenage characters on "Stranger Things" differ in age from the actors who play them.

Actress Millie Bobby Brown is 16 years old, while her character Eleven should be about 14 on the show.

When Eleven was first introduced on the show, we didn't know her exact age — only that her mother had been trying to find her for about 12 years.

Now that about two years have passed, that would mean Eleven is approximately 14 years old. 

Finn Wolfhard is now 17 years old, though his character Mike Wheeler is meant to be around 14.

Like Eleven, Mike and his friends should all be just about 14 years old. They graduated from middle school between seasons two and three, and are just about to start high school by the end of the latest season.

Noah Schnapp is currently 15 years old —just a shade older than Will Byers on "Stranger Things."

Of all the actors and their fictional counterparts, Schnapp is currently the closest matched with his character.

Caleb McLaughlin is 19 years old, while Lucas is around 14.

Just like the rest of the friend group, Lucas is about to start his freshman year of high school on "Stranger Things." But McLaughlin is almost 19 years old, and was the first of his costars to get a driver's license.

Thirteen-year-old Priah Ferguson plays Lucas' 10-year-old sister, Erica.

Erica is heading into middle school, taking over the role of youngest nerd on "Stranger Things" now that the boys have aged up. 

Sadie Sink is 18 years old, while her character is around 14.

Just like the young actor who plays her on-screen boyfriend, Caleb McLaughlin, Sink is a bit older than her other teen costars on "Stranger Things."

Dacre Montgomery, 24, played Max's brother Billy, a recent high school graduate.

Billy arrived to Hawkins and joined the other older teens in high school last season. We're pretty sure he was in Steve Harrington's grade, which means he would've graduated just before the start of "Stranger Things 3" and is around 18 years old.

Gaten Matarazzo is 17 years old, and plays 14-year-old Dustin Henderson.

Once again, Dustin should be around 14 on the third season of "Stranger Things" as he heads into high school for the first time.

Joe Keery is 28, while his character Steve Harrington just finished high school and is about 18 years old.

Keery's character Steve has become friends with the younger teens on the show and looks after them. In real life, the actor is a decade older than all of his costars.

"Stranger Things" newcomer Maya Hawke is 22 years old, and plays 18-year-old Robin.

Like Steve Harrington, Robin's character just finished high school and is therefore around 18 years old. 

Twenty-three-year-old Natalia Dyer plays high school senior Nancy Wheeler.

Nancy is just about to start her final year of high school, which means she's around 17 or 18 — about five years younger than the actress in real life.

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