Hi springflowers - welcome to the lovely world of small furries, would receommend you read some of the thread on here, which may help answer some of the queries you have - lots of folk on here with lots of experience and helpful hints - you will get a taste of what guinea life is like!
In general, guineas really don't do temperature extremes, so to bring them in and out when it is so cold would probably make them ill- their little bodies just cannot adjust and damp conditions can make them quite ill. IF you have space inside, I would suggest you do try and get them inside where possible, away from direct heat, but somewhere where they can have a little explore and be warm inside. Plenty of people do keep them in outside shelters or garages, but this is tough going when the snow starts as they will need to be very snuggled up.
It is a really tough time for guineas, they can't be outside in their run as the grass is often too wet, and they do need exercise and to be occupied if you know what I mean . They do like 'cuddle time' - may be a regular routine where you and your daughter wrap them in a cuddle cloth, tempt them with food and they get used to your company, but even if you keep them in a room where people are coming in and out, they get used to the sounds.
They are very interactive and sociable creatures, and I think it is a shame that they are kept away from family, though fully understand why, it just isnt practical for everybody to keep them indoors, but they are not terribly 'hardy' so it is best to be safe with them and try and keep them warm and sheltered.
Hope this helps - feel free to keep asking, others will help you!