I totally understand the worry about separation anxiety, because my girl was exactly the same when I first enrolled her in playgroup, she clung to me so hard the first few weeks. What really helped us was choosing a centre that allowed me to stay in the classroom for the first few sessions so she could slowly get used to the environment without feeling abandoned. When you visit the shortlisted playgroups, do ask the teachers how they handle separation anxiety specifically, because a caring and experienced teacher makes such a big difference. Also check the class size, smaller groups tend to be gentler for sensitive little ones who need more one-on-one attention. Take your time to visit a few places in Yishun before deciding, and trust your gut feeling when you see how the staff interact with the children. You know your LO best, so go at her pace and she will get there lah.