Display/Hide part of a list - asp.net

Question

I have an (unordered)list (generated by a repeater) of items. However, I'd like to show the first three items, and have the rest hidden by the main content div. When a button is pressed, I would like the list's div to expand, pushing the main content div down and showing the rest of the list. I was thinking of using slideDown(), but that closes the entire div ( and I would like to show the first 3 items of the list). What would be the best way to achieve an effect like this? Is there a plugin that can easily show X items of a list and the display the rest upon request?
Thanks
edit: Adding current code:
<div id="name_links">
<asp:Repeater ID="rptName" runat="server">
<ItemTemplate>
<ul class="ul_links">
<li>
<a id="aName" runat="server" href=<%# Eval("Name")%> >
<%# Eval("Name")%>
</a>
</li>
</ul>
</ItemTemplate>
</asp:Repeater>
</div>
<div id="main_content" >
...
</div>
I've tried to add this JQuery, but it doesn't seem to pick up any of the links:
$("ul.ul_links").each(function() {
$(this).children("li:gt(3)").hide();
alert("Testing"); //This never gets called.
});

Answer 1

You item template looks wrong
It should be
<div id="name_links">
<ul class="ul_links">
<asp:Repeater ID="rptName" runat="server">
<ItemTemplate>
<li>
<a id="aName" runat="server" href=<%# Eval("Name")%> ><%# Eval("Name")%>
</a>
</li>
</ItemTemplate>
</asp:Repeater>
</ul>
</div>
Then jquery will be able to show and hide as desired.
The other way you were creating sets of ul -> li tags .

Answer 2

This can be done with jQuery, but it would help to see example of your markup.
Here's a link showing how you could do it with ul/li tags. You should be able to adapt it to your own markup without too much trouble.
Typically you hide item 4 and out with:
$('div:gt(2)').hide(); //index starts at 0
You have to modify the jquery selector to fit your markup and you could put it in a $(document).ready() block in order to hide the items on page load.