As soon as a seed germinates, it needs light, or else they get "leggy," which is what you have. You need a light fixture if you are starting them indoors, but you can use any kind of fluorescent light. They are cheap. You can screw a spiral cfl bulb into any inexpensive desk lamp and make it a grow light for seedlings. You will also need a small fan to move air in the room. They need a gentle breeze, or that can also make them leggy. I would just yank those and start over.

My best luck with cool weather crops outdoors in hot weather has been under a deck on a concrete pad. They like the shade and the concrete helps keep the roots cool. The small rockwool cube by itself is not great for the hot weather, because it heats up so quickly. If you move them into a system with a lot of mass, like a deep water culture setup, that will help your roots not get too hot.

*What he said*

You need throw those away and get the next seedlings under full sunlight or an indoor setup. Those will not turn out well with how leggy they're already.