Add an event calendar to your website! Great for fitness centers, community centers, organizations of any size. Create event categories for easy sorting.
More info:
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View a demo here: http://www.creativegraymatter.com/calendar
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For more information check out http://www.creativegraymatter.com/blog/wordpress-events-calendar
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CGM Event Calendar

Creates a classes and events calendar for your site.  Handles repeating entries and provides multiple views.

Fabio Pacifici

The Fab Lectures Plugin customise your WordPress admin panel with a custom “Lectures” menu, useful to achive your favourite lectures, specify a year and or a class you might have followed as part of the lecture. 
REST API ready. Designed to work with the official WordPress 2019, 2020 themes and now compatible with other themes.
Features of the plugin:
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<li>Adds Lectures Post type to the wordpress admin panel.</li>
<li>Adds Year, Class, Category, Tags to the lecture.</li>
<li>Custom Lecture templates </li>
<li>Tested up to 5.3</li>
<li>Designed to work with the WordPress Twentynineteen, Twenty Twenty and other official themes</li>
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<h3>Arbitrary section</h3>
This plugin Requires WordPress Twentynineteen theme.

Fab Lectures for WordPress

The Fab Lecture Plugin for WordPress adds a new menu to your admin panel "Lectures" useful to achive your favourite lectures.

CGM Event Calendar vs Fab Lectures for WordPress