Present Tense: point / points

The teacher points at the whiteboard. 

Present Continuous Tense: (be) pointing

He's pointing at a word on the whiteboard.

  The teacher is pointing at a word on the whiteboard.

Past Tense: pointed

He pointed at something important.

Infinitive: The teacher uses his finger or a stick to point at things on the board.

Gerund: Pointing at words on the whiteboard helps students understand new ideas.