为什么我不能在for循环内声明``var highScore = 0;`''

Hi when i try to declare var highScore = 0; inside for loop in chrome console it says Uncaught SyntaxError: Unexpected token 'var' so what can i do for that here is my code:

var scores = [60, 50, 60, 58, 54, 54,
              58, 50, 52, 54, 48, 69,
              34, 55, 51, 52, 44, 51,
              69, 64, 66, 55, 52, 61,
              46, 31, 57, 52, 44, 18,
              41, 53, 55, 61, 51, 44];

var totalTest = scores.length;

function bubbleScore() {
  for (var i = 0; var highScore = 0; i < scores.length; i++) {
  console.log("Bubble solution #" + i + " score: " + scores[i]);
  if (scores[i] > highScore) {
    highScore = scores[i];
  }
  }
  console.log("Bubbles tests: " + scores.length);
  return console.log("Highest bubble score: " + highScore);
}
bubbleScore();