While Ishaan's parents are driving home, after receiving his poor academic report, his mother laments "I teach him myself. All day it's 'Ishaan! Ishaan! Ishaan!'". But, when she says the third "Ishaan" word, her lips are closed.
When Rajan and Ishaan are talking in the corridors, Rajan says he lives in the staff quarters as opposed to in the normal student dorm. Later on, Ram asks Rajan where Ishaan is, and Rajan says he saw him leave the student dorm early. If Rajan lived in the staff quarters, he wouldn't know this.
When Ram Shankar( Aamir Khan) ask Ishaan's father Mr Awasthi to read the name of the video game, he responds that he can not read because it is in Chinese. In reality it is in Japanese (Chinese does not have Furigana and Katakana). But it maybe possible that Mr Awasthi couldn't distinguish between Chinese and Japanese.
When Yohaan opens the door to get the newspaper and milk on Sunday, he has his knapsack slung on his right shoulder. Immediately after this, he goes to Ishaan's door and says, "Inu, Papa aa gaye." His bag can be seen slinging from his left shoulder at this time. However, again when Ishaan is sitting with his father and Yohaan leaves, his bag is again seen slinging from his right shoulder.
The absent note found by Mr. Awasthi (Ishaan's father) which was written by Ishaan's elder brother was actually written in Ishan's school diary. While Mr. Awasthi finds a rolled scroll absent note in the house.
During the song "Jame Raho," which portrays the busy and mechanical life of the family, Maya is shown ironing a striped short for Nandkishore. Next cut, he is shown actually wearing a plain shirt instead of the just hurriedly ironed shirt.
During the scene in which Ram goes to visit Ishaan's parents, he is stopped at a bus station and sees a kid serving tea, a man with a black shirt walks behind him. The shot cuts to Ram and then back to the kid serving tea doing something different, but that same-black shirted man is walking behind him.