Books like St. Clare's, The First Year
Enid Blyton
St. Clare's, The First Year is 182 pages, about 3 hours 20 minutes at 250 words a minute.
6 books to read next
How long each takes
The Third Form at St Clare's 2.8 h 
The Lost Twin 5.4 h 
Whispers in the Walls 5.3 h 
The Sixth Form at St Clare's 2.9 h 
The Dance in the Dark 5.9 h Leaving Home 2.9 h Bar height shows length. Estimated at 250 words a minute.