If you wish to keep your American number at home you can sign up for a Stay Local number (what is a stay local number?).
Once you receive the Stay Local number, you can call your provider in America and ask them to call forward your number to the Stay Local number we provide you with.
Make sure to do this as close to your date of departure as possible, because once your number has been forwarded all calls made to that number will go to your number in Israel.