One of my biggest pet peeves is sitting through a meeting or training with a poorly designed Power Point or Slide deck. It doesn't capture my interest, it looks blazé, and I spend my time thinking of how unprofessional the presentation actually comes across. Now I understand that not everyone has a background in graphic design, so allow me to introduce you to SlidesCarnival.
According to the company, "SlidesCarnival templates have all the elements you need to effectively communicate your message and impress your audience, and completely free!". The benefit of Slides Carnival is the option download the Google Slides or Powerpoint version of the slides, while those featured here are all formatted for Google Slides.
Here are a few go-to templates for classroom lessons and conference workshops, but I always suggest heading over to check out their collection of professional slide templates that are updated frequently.
Enjoy, and get creative!