In Dutch, a party for your class is a klassenfeest, with a linking n and written as one word. This is also correct when just one class attends. The article is het: het klassenfeest and het schoolfeest.
Why does klassenfeest have an n?
The word combines klas and feest. The plural of klas is klassen, so this compound takes a linking n. The number of classes attending does not affect the spelling. Taaladvies.net explains the Dutch linking sounds.
Klas and klasse
One klas, two klassen. Klasse, meaning a category or level, also has the plural klassen. For a party with school classmates, write klassenfeest. Klassefeest can be a deliberate pun about a “classy” party, but it is not the usual spelling for a class party.
Two examples for a Dutch invitation: “Vrijdag vieren we ons klassenfeest” and “Kom je ook naar het klassenfeest van groep 8?”
De or het schoolfeest?
It is het schoolfeest. Feest and klassenfeest also take het. A klassenfeest is for a class; a schoolfeest can involve several classes or the whole school.
Planning the party
Start with the date, venue and number of children. Agree on supervision, the finish time and where parents collect their child. Then choose suitable music and a few activities. Ask the children for favourite songs beforehand.
Try one or two dance games. For a final primary-school celebration, see the school leavers’ party. For several classes, read about a school party.