Well, 30 crickets a day is pretty good for an 8 wk old, do you feed them live food 2 to 3 times a day? Only 10 crickets a day is no where near enough. Babies usually eat between 30 and 100 crickets a day each. Feeding mealworms really isn't a good idea because they don't have much nutritional value and have a hard chitin shell which can cause an impaction, especially to a baby. You might want to consider getting phoenix worms, horns, butters, silkworms or even dubia roaches. All of those are much better than wax worms & mealworms. Are they eating any greens/veggies? What ones do you offer?
So, they each have a Repti-Sun fluorescent? Is it placed within 6 to 8" from their basking spots so they can get the benefit of the UVB and basking bulb at the same time? Yes, it's a must that you get a good thermometer, temps are critical, especially for babies. Are your basking bulbs white or colored bulbs?
Since you are sprinkling the calcium on the crickets when you get them, you would be better off shaking about 1/2 dozen crickets at a time in a small amt of calcium in a plastic bag, then feeding them right away so that the calcium is still on them. It's also important to gutload your crickets so that the beardies get the benefits of well fed crickets.