Scaling images for tablets and smartphones

I’m running this website, using the tewntyeleven theme. The pages look well with a few exceptions. On the front page and one other page, I have pictures laid out in a table. On my tablet and the smartphone, those images/tables seem to mess up the design. They are apparently not scaled down. The image size is set to 100% and their width and height are set to auto. What else can I try?