Participles Adjective and Verb in a Sentence.

[JDragon]

I have doubt in these two sentences I have created.

1. The teacher smiling is standing next to the boy explaining a math problem.

In this sentence I want to convey this message : the teacher is smiling and standing next to the boy who is explaining a math problem.

2. The teacher smiling is standing next to the boy explaining a math problem.

In this sentence I want to convey this message : the smiling teacher is explaining a math problem to the boy. I don't want to use "him" in the above sentence.

I think both the sentences are correct but I fail to understand what messages they convey. please explain.

[Tukanja]

I would rather say it as below.

1) With a smile on his face, the teacher is standing next to the boy explaining a math problem.