Okay, good advice given here but I'll add my 2ยข worth...
Deb/dmurray, your plants have been too far from your lights from Day One. The tall dome on your mini-ghouse caused the plants to be way lower than they should be. The dome is also a bit yellowed w/age, also reducing the light strength (or so it appears on my monitor.) Your seedlings need to be within inches of the light as soon as they declare (appear above soil.)
Your elongated/tall stems and lack of strong light have kept the plant from moving on to it's next growth stage - foliage growth.
By the way, you should move your plants where they are under the center of the light, the middle portion, not at one end or the other. The strongest light will be in the center of any fluorescent bulb with weaker light rays towards the ends. This is why it is good to move trays under lights back and forth so they each get some of the stronger light off and on (if you do more than one tray next time.)
I bet you may have some decent root growth, as long as the soil medium hasn't been too wet during this time. If your soil level is fairly shallow you'll see your roots have grown outwards, probably in abundance (unless, again, your soil is too wet.) If your soil level is deeper you'll see the roots have grown more downward but with a smaller amount of roots.
I'd do exactly as Ken suggested and do a VERY light liquid feeding, highly diluted, but I think I'd wait a couple days after you improve the lighting AND, as someone else mentioned, put a gentle fan on the plants for a short period of time. It is probably still too cold to set them out in direct sun in your area...I can only imagine it is cold as cubes in Minnesota. (Brrrrr....) Maybe you have a bright window you can move them to for a couple hours, keeping in mind to watch them so they don't get burnt from the abrupt light change.
Lastly, since they are peppers (and tomatoes) you'll see faster growth if you leave the heat mat turned on (but remove the dome.) Peppers really need the heat or they just slow down their growth rate tremendously. The last thing you want right now is cooler soil.
Sorry to be so long-winded. (I was giving Rick Corey competition~!)
Shoe (rained in and computering for a while!~)
