Konstantin Kovshenin

Create a column group with the <code>[column-group]</code> shortcode, then add columns to the group with the <code>[column]</code> shortcode, like this:
<pre><code>[column-group]
 [column]This is my first column[/column]
 [column]This is my second column[/column]
[/column-group]
</code></pre>
You can also span columns, like this:
<pre><code>[column-group]
 [column span="2"]This is my first column spanned across two columns.[/column]
 [column]This is my second column[/column]
 [column]This is my third column[/column]
[/column-group]
</code></pre>
The first column will be twice as large as the second or third.
Styles are in columns.css. If you’d like your own margins and stuff, dequeue the columns.css style during <code>wp_enqueue_scripts</code> with a priority of 11 or more.

Columns

This WordPress plugin boosts your website with... you guessed it, columns!

Sergio Costa

A WordPress plugin which you can manage column sizes with shortcodes. 
It is a 10, 12 and 16 columns Grid System.
Made with SASS

SC GridSystem

A WordPress plugin which you can manage column sizes with shortcodes.

Columns vs SC GridSystem