Talking and understanding?

Annamaria

So my kid apparently only talks at school. When he’s with me he will say mama dada ok oh no and tada “which means everything from Hi, bye, and here you go- when he hands me something” but when I ask him to show me where his eyes mouth nose are he points to them. And I’ll tell him to clap and he will. And he knows his snacks are in his book bag- he will drag the bag to me when he’s hungry or thirsty. He just won’t say any other words to me. And I say the words out loud whenever I give him something to try to have him repeat me. His school told me he doesn’t talk much because he knows he he can get away with the minimal with me but at school he has to work for it. Is anyone else dealing with this? I’m worried for his 18 month apt. Every other milestone he’s hitting and he’s even starting to pull at his diapers when they need to be changed.