app/views/emails/index.html.erb
<div class="alternative-options-links">
[<%= link_to 'plain text', organization_emails_path(format: :txt) %> |
<%= link_to 'csv', organization_emails_path(format: :csv) %>]
</div>
<h1>Students in <%= @course.title %></h1>
<table class="table table-striped">
<tr>
<th>
Username
</th>
<th>
Email
</th>
<th>
First name
</th>
<th>
Last name
</th>
</tr>
<% @students.each do |student| %>
<tr>
<td>
<%= link_to student.username, participant_path(student) %>
</td>
<td>
<%= mail_to(student.email) %>
</td>
<td>
<%= student.field_value(OpenStruct.new(name: 'first_name')) %>
</td>
<td>
<%= student.field_value(OpenStruct.new(name: 'last_name')) %>
</td>
</tr>
<% end %>
</table>