Whoever is going with us should meet at my house at 8:00 a.m.
Explanation:
A noun clause contains a clause which acts as a subject, and usually begin with <em>wh-</em> words, such as <em>what, that, how, when </em>and <em>why</em>. Thus, the noun clause in the sentence is <em>Whoever is going with us</em>. In fact, it consists of a subject and a verb, and at the same time it functions as the subject of the predicate <em>should meet at my house at 8:00 a.m.</em>