What was the temperature range of the yeasts you used? I would get them at least into that range to try and get them to carbonate. I would also try to get them at least close to 70F so that they can carbonate a bit quicker. Most books say to carbonate around 65F. Probably because most yeast are at least active at that temperature. Far less are active (strains of yeast) in the 56F area.
What's the warmest room in your house? What's it's temperature range? If you can at least get the brew into that area, where it's closer to 70F for a good part of the day, it will speed things up.
For instance, I bottle carbonate in the living room/tech central since it's close to 70F for most of the day time. Either due to the sun coming in and warming the room, or the computers running. I DO have the bottles in boxes, to keep out that last little bit of light.
You could cover yours with heavy blankets once you get them into a warmer room. That should help stabilize the temperature they're at. Just try to keep them away from cold drafts.