You need to get them a thermometer and keep the tank temp at about 80-85F. You also should make sure where the heating pad is only covers a small portion and they don't lay on it too much. They can get thermal burns. And no they won't always move when it starts to get too hot thats why you need to monitor it. Temp is very important with these guys...it can mean the difference for them eating and getting upper respiratory infections. They shouldn't be fed if they are cold or they will have difficulty digesting and could possibly become impacted. Secondly, if you aren't "gut loading" your crickets prior to feeding them to your dragons for better nutrition. Here is a suggestion on how to gut load:
When you buy crickets, feed them well ("gut-load" them) before offering them to your dragon. Crickets from some sources may have subsisted on paper and are starving when you get them; others may have been overdosed with vitamin A preparations (which will depress calcium metabolism). Chicken laying mash is high in calcium and makes a good cricket diet. A good home-made cricket diet includes dried grain (e.g., oatmeal), milk powder, low-protein dry dog or cat food, dried alfalfa (grass or pellets), vegetables (e.g., leftover veggies uneaten by your dragons), and a piece of orange or potato. An even better alternative is the excellent cricket food sold by Ronnie Buck is highly recommended. Keep wet items in a separate dish and change them often to avoid mold. For moisture, you can include a damp sponge; crickets promptly drown in any open water source.
Also feed veggies every day and crickets every other day. Check out this site for more bearded info :
Tosney's Bearded Dragon Care
Hope this helps