The old computers -> Las computadores viejas/antiguas [in Spain they would say Los ordenadores viejos/antiguos, ordenador = computador/a}
Some interesting books -> Unos libros interesantes
The ugly backpack -> La mochila fea
A big notebook -> Un cuaderno grande or Un gran cuaderno (it's the same thing, but the from of the adjective changes depending if it's before or after the noun)
A funny friend -> Un amigo gracioso
The nice teacher -> La maestra amable/simpática (it can be translated into Spanish in different ways, depending on what you want to say specifically).
The boring homework -> La tarea aburrida
Some adventurous students -> Unos estudiantes intrépidos (you could say "atrevidos" but that can mean another thing, in Spanish "atrevido" can <em>sometimes</em> mean "insolent", "intrépido" is always positive.)
