One professional development training I have experienced that I felt was very effective, helpful and made a difference to my practice is  a STREAM (Science, Technology, Research/Reading, Engineering, Math) workshop I attended. This workshop was very interesting and informative, having received such wealth of knowledge at my centre the teachers started practicing all that was learnt, by doing fun experiments with the children. The children are always eager to participate in the experiment and excited to observe the outcome. Also, STREAM  is used in our planning sessions as well as incorporated  the daily activities.