General:
* Nagpapaisip sa akin - This literally translates to "makes me think" and is a good general translation for "makes me wonder."
* Nagtataka ako - This means "I am wondering" and focuses on the act of wondering itself.
More specific:
* Pinag-iisipan ko - This means "I am pondering" and implies a more thoughtful, deeper wondering.
* Napapatanong ako - This means "I am asking myself" and suggests a more inquisitive wondering.
Informal:
* Napaisip tuloy ako - This means "I am suddenly wondering" and implies a spontaneous thought triggered by something.
The best translation will depend on the specific situation and the emotion you want to convey.