 <p>You can use params to specify <code>start_year</code> and <code>end_year</code> of your select. Example:</p> <pre><code>&lt;div class="field"&gt; &lt;%= f.label "Fecha de nacimiento:" %&gt; &lt;%= f.date_select :fecha_nacimiento, :start_year =&gt; 1950, :end_year =&gt; (Time.now.year - 10) %&gt; &lt;/div&gt; </code></pre> <p>Look at <code>:end_year</code>, I used <code>Time.now.year - 10</code> because I assumed that the minimum age to register is 10 years old.</p> <p>Boa sorte =]</p> <p>Reference: <a href="http://api.rubyonrails.org/classes/ActionView/Helpers/DateHelper.html#method-i-date_select" rel="nofollow">http://api.rubyonrails.org/classes/ActionView/Helpers/DateHelper.html#method-i-date_select</a></p>