return list of objects from checkbox

I'd like to return a list of Personnes from checked checkbox in my view and get it in my controller but selectedObjects count is always 0...

Here's my view with checkboxes:

<tbody>
    <tr>
        <td>
            @foreach (var p in Model.Personnes)
            {
                <ul>
                    <li>
                        @Html.DisplayFor(model => p.NomPersonne) @Html.DisplayFor(model => p.PrenomPersonne)
                    </li>
                </ul>
            }
        </td>
        <td>
            @using (Html.BeginForm("Presence", "Evenement"))
            {

            foreach (var p in Model.Personnes)
            {
             <ul><input type="checkbox" name="selectedObjects" value="@p" /></ul>
            }
             @Html.AntiForgeryToken()
            <input type="submit" value="Valider Presence" class="btn btn-primary" />
            }
        </td>


    </tr>
    @*<tr class="form-group">
        <td class="col-md-offset-2 col-md-10" align="right">
            <input type="submit" value="Valider Presence" class="btn btn-primary" />
        </td>
    </tr>*@
</tbody>

my controller:

[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Presence(List<Personne> selectedObjects)
{
    return View(selectedObjects);
}