Calendar module is one of the most useful modules in Drupal. It allows to create and view different events in time. Equally important module is Printer-Friendly which allows to have Print link and formats page in a printer-friendly style.

Unfortunately, Printer-Friendly module only works with node pages and calendar views are Views module pages so printer-friendly does not work with them. Following is a quick tutorial (inspired by Chill35's suggestion) on how to create printer-friendly pages for Calendar. Actually, the trick can be used for any views page, with some modifications.

The essence of the trick is that when we need a printer-friendly version of a page, we add "printit" to the end of the URL and when it is in the URL modify CSS accordingly to strip-off header/footer/etc. In Calendar module's case (which is actually called "events") you need to edit event_link() method in event.modules file.

In there, at the section where links are generated ( "elseif (user_access('access content')) {" section ) insert the following snippet:

-- snippet --

$curLink =  $_SERVER["REQUEST_URI"];

    // We gotta have full URl to do printer-friendly trick.
    // If we do not have one, we gotta construct month view.
    if ( !strpos ( $curLink, "all/")) {
        $links['Printer-Friendly'] = l(t('Printer-Friendly'), $base .'month/'. 
        $node->filter.'/printit', array('title' => t('Printer-Friendly')));

    if ( !strpos ( $curLink, "printme") && !$links['Printer-Friendly']) {
        $links['Printer-Friendly']  = l(t('Printer-Friendly'),  
        $curLink."/printit", array('title' => t('Printer-Friendly')));

-- snippet --

This will add Printer-Friendly link to the links and only show it when you are not already in the printer-friendly mode.

Then in page.tpl.php of your Theme, in the head section, insert:

    $curLink =  $_SERVER["REQUEST_URI"];
    if ( strpos ( $curLink, "printit")) {    

        print theme('stylesheet_import', base_path() . 
            path_to_theme() . '/print.css', 'all');     

And the print.css file that you put in themes/ folder may look something like:

.header, .bar, .right_articles, .left_articles, .footer,  .event-filter-control, .feed-icon {
    display: none;