The series received generally positive reviews from critics, with praise for its darker tone, writing, themes, characters, and acting.

[1]The programme is set in Coal Hill Academy, a fictional school that has been featured in Doctor Who since the 1963 serial, An Unearthly Child, and focuses on six of its students and staff members.

[2] They have to deal with the stresses of everyday life, including friends, parents, school work, sex, and sorrow, but also the horrors that come from time travel.

The Doctor and his time-travelling have made the walls of space and time stretch thin, and monsters are planning to break through and wreak havoc upon the Earth.

[19] Greg Austin, Fady Elsayed, Sophie Hopkins and Vivian Oparah star as four Sixth Formers, with Austin playing a character named Charlie, while Katherine Kelly portrays Miss Quill,[25] a Coal Hill Academy teacher.

[13][26] Nigel Betts reprises his role as Mr. Armitage from "Into the Dalek", "The Caretaker" and "Dark Water" from the eighth series of Doctor Who.

So good, in fact, that even after only two-thirds of its very first season, it’s possible to see the show’s potential bubbling over the sides like an over boiled pot of pasta.

[60] Despite being critical of early episodes, IndieWire gave the series as a whole a positive review, stating "while the show knows how to juggle the heavier issues and high-concept scenarios, it doesn’t skimp on the fun."

They highly praised Kelly's performance, calling her "fabulous", and the characters of Miss Quill and Matteusz, considering them "absolute scene stealers".

As is the case with good teen horror dramas that has come before it, Class' scariest, most interesting villains aren’t alien monsters that wipe out entire civilizations, but rather the real-world problems like losing a parent, a girlfriend, or losing the time and space to simply be a kid."

[...] The most successful parts of the series explore the ways the students support one another through all the weighty challenges they’re faced with, both of the real-world and sci-fi variety.

In fact, I found myself wishing there had been more than just eight episodes in the first season because it would’ve been nice to have seen a bit more of the group’s lighthearted side.

[61] The Los Angeles Times gave the series a mixed review, stating that Ness' storytelling felt "muddled and mechanical" and "tells you too much, too fast."

[55] In a post-cancellation review of the series, Morgan Jeffrey of Digital Spy debated the reasons the series was unsuccessful in finding an audience, called the show "the spin-off no-one asked for", and argued that the reason it failed in ratings was due to the BBC not knowing who the show was for: "A teen-oriented drama with adult themes, spun off from a series intended (primarily) for children, the tone of Class was every bit as confused as that muddled origin would suggest.

The show absolutely had its gripping moments, its standout episodes (the poignant "Nightvisiting" was a clear highlight) – and, oh, what a cast.

[63] Among the plans were a theme of extreme compromises for the sake of love (with a storyline involving Charlie losing his soul to save Matteusz), a civil war among the Weeping Angels, and the addition of new writers Kim Curran, Juno Dawson and Derek Landy.

Big Finish Productions has produced audio dramas based on Class that take place during the run of the TV series.