A class observation day was scheduled to be held in Gaku's class. However, Gaku was worried that if Hayato took a day off to attend, it would cause inconvenience at his workplace and increase his workload.
Waka and Grandpa both understood that,
so that's why they're helping him!
Waka y el abuelo lo entendieron
y por eso decidieron ayudarlo.
Waka et papy le savent bien,
c’est pour ça qu’ils garderont le secret !
Waka e il nonno l'hanno capito, 
ed è per questo che lo aiutano!
O Waka e o vovô entenderam isso.
Por isso estão ajudando!
Вака и дедушка это понимают,
поэтому решили помочь!