This piece of jQuery will calculate the height of columns and resize the shorter ones to be the same height as the tallest one.

equal-height-columns.js

function equalCols() {
  $('.js-cols').each(function() {
    var tallestCol = 0;
    currentHeight;
    $(this).find('.js-col').each(function() {
      $(this).css('height', 'auto');
      currentHeight = $(this).height('auto').height();
      if (currentHeight > tallestCol) {
        tallestCol = currentHeight;
      }
    }).css('height', tallestCol);
  });
}

$(window).load(function() {
  $(this).resize();
}).resize(function() {
  equalCols();
});