When the mother returns home late one evening with sushi, she gets a glass of water from her daughter and drinks it nearly empty. After a brief intermediate shot, she is holding the glass again but now it's more than half full.
In the long shot of the mother dusting out the comforter, she swings the carpet beater with her right hand. After the cut she makes a last beat with her left hand.
When Akira buys the stack of chocolates for Yuki near the end of the movie, he buys 19 boxes and the total comes to 1,895 yen. As there was no sales tax at the time Japan, each box would have to be priced at 99.74 yen - which is essentially impossible.