This multiple case study explored early childhood educators' implementation of a suite of play-based mathematics activities with children aged 3 to 5 years in six different early childhood education and care programs in Melbourne, Australia. Educators approached the enactment of the activities differently; however, those educators who used the activities reasonably frequently and with attention to the underpinning mathematical concepts reported an increase in their self-confidence in supporting children's mathematical thinking. For these educators, increasing self-confidence, in conjunction with children's enthusiasm, led to increased frequency and further gains in self-confidence. Some educators did not implement the activities and no change in attitude was observed. New ways to support early childhood mathematics teaching practice, as a means to challenge entrenched attitudes and beliefs, are needed.