It sounds like she is posession guarding. Be sure to work with her a lot, playing with her toys with her, practicing bite inhibition with ropies, and don't tolerate growling towards you. Some dogs cannot get over this with other dogs, if she's a rescue there could be issues in her past with dogs stealing her food/posessions. Ask the daycare if she could possibly play with no toys around, or only ropes and large sharable toys like you said.