Put this shell to your ear and you’ll hear the sound of the waves.
We played a game trying to guess who was lying during lunch break.
I wanted to say, "I hit the ball really well with my bat," but I accidentally said butt.
You know that the kanji 当 means right or success. So since this is a verb, you're doing right and success (which doesn't make much sense). Instead, you're guessing something and getting it right. So, this word means to guess or to guess something. Hopefully you don't have to guess too hard when it comes to the meaning of this word as well.
The reading can be remembered via the word 当たる which you learned a few levels ago. Use that knowledge to remember that this word is read as あてる. The important part is the あ.