さあ、どいう意味かな～ (Sorry, couldn't resist XD ) かな is an informal grammar form that can most directly be translated as "I wonder..." It's mainly used to show uncertainty. Some common applications are talking about the weather, whether you did well on an exam, whether someone will like a gift, etc. かな can also be used in a joking manner to show you already know the answer to a question. It is the same as how "I wonder" expressions are sometimes used sarcastically in English, . Reference: http://www.jgram.org/pages/viewOne.php?tagE=kana

According to the textbook "なめらか 日本語会話 " かな is often used when thinking aloud or in informal conversations as a substitute for a normal interrogative sentence

For example in the this sentence : はるの学校かな?