You can plan a professional development day by scheduling staff for an entire work day of training and preparing a slate of learning activities to enrich their professional credentials. The day can serve as a concentrated effort to bring an entire staff up to standards on a particular topic or as an organized opportunity for the staff to gain knowledge and continuing education credits during work time. Although the day has many of the same trappings as a conference, it is distinguishable because it is typically organized by an employer, takes place as a substitute for an ordinary day of work, and is arranged to satisfy a work-related credentialing requirement.
Perhaps the most structured use of professional development days is in teaching at the compulsory school level. In the US in particular, school districts are required to have professional development plans for their teachers that ensure each one is adequately progressing in the continuing education requirements for teacher credentialing. The teachers have to amass a certain number of educational credits every year to hone their skills. Districts and individual schools organize days where the children are off from school, but the teachers attend a day-long series of trainings and seminars that award continuing education credits all at one time.
To plan a professional development day, it is typically best to first establish an event committee. Then, pick a date and find a location that can accommodate a large number of people and simultaneous educational sessions. If the day will benefit a specific group of workers, such as teachers, reserve the day for professional development on the work calendar. This conveys to staff that they will be reporting to work as usual but will be engaged in different activities.
A professional development day can also be organized in a non-compulsory environment. Trade associations that credential their members often arrange days that provide multiple educational opportunities for credits. If you organize this type of event, you would set the date and rely on member registration rather than required attendance that substitutes for a day of work. The date could be set during the week and serve as a substitute for a work day if an employer allows, or set on a weekend or off day and occur on a member's free time.
You will have to decide whether you want the professional development day to address a particular topic or have a theme. Conversely, the day can have an amalgamation of topics that coincide with the school's professional development plan. Arrange for guest speakers or trainers to conduct the topical sessions and finalize an agenda. Finally, use your committee to manage the incidentals of the event, such as arranging for food, making photocopies, and plan for contingencies.