Why bother praying when G-d does what he wants anyway? Prayer, personal responsibility and G-d's will are all factors when dealing with life's issues, according to Rabbi Ze'ev Leff, the rabbi of Moshav Matityahu and the Dean of the Post High School Yeshiva of Matityahu. In an interview with Israel National Radio's Judy Simon, Rabbi Leff explained that G-d listens to people's prayers, but that His plans are contingent on human behavior. The interview was part of Mikdash Kids, a new radio show geared towards Jewish youth.
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Using the analogy of a man dying in a hospital, Rabbi Leff said, "Plan A is for the man to die within 2 hours. Plan B is for him to undergo a painful operation with a long recovery, but then to continue a healthy life for 50 years." 
"We change and strengthen ourselves if we pray. G-d's plans stay the same. The choice is ours."
Rabbi Leff added that there was a Plan C, too. If the man worked on strengthening his body through exercise, he could avoid the operation altogether and simply take a bitter medicine to recover, in place of the surgery.
He added that there are also ways to "sweeten the medicine".
"Our prayers are like that exercise," he explained. "We change and strengthen ourselves if we pray. G-d's plans stay the same. The choice is ours."
Judy Simon hosts Mikdash Kids every Wednesday at 6:00 PM on Israel National Radio. Mikdash Kids is an educational program for kids and adults about Jewish heritage, holidays and the Torah portion of the week.