recognize their work and thank them for it. genuine appreciation goes a long way. competition is never friendly ... it does boost the performance for a month or so, but you have to be a very good judge to cover all team members and still acknowledge their individual work infront of everyone.
Ask some questions such as: are they happy in what they are doing? Is there something they need to learn? Something they need help with? Something they need more training in? Something they like doing that they could maybe do more of? Something they see that could be done better? Are there clear goals and measurements for their work? Do the team understand their part in contributing to the organisation's work? And yes, acknowledgement of good current performance is always welcome.