"We are as studious as you."
Translation:Somos tan estudiosos como tú.
Hilary, in Spain you have four forms of addressing: tú, vosotros, usted and ustedes. Tú (singular) and vosotros (plural) are informal addressings, while usted (singular) and ustedes (plural) are formal.
In Latin America, the vosotros addressing is not used, and when you talk to a group of people there, you'll use ustedes, no matter if you have a formal relationship or not.
Some countries in Latin America also use the vos form, which is different from vosotros. Vos is used to talk to a single person informally, so it's a lot closer to tú. In some places, vos replaces tú, and in others they coexist.
Paul, please note that estemos would be the Subjunctive form, which wouldn't work here. Estamos is the form you want.
In this sentence we're talking about a characteristic of someone. Talking about characteristics uses the verb ser. Estar would be used to talk about conditions instead.