¡Es fácil! offers you various free exercises to improve your skills with Spanish language:

Numbers

Do you already know how to count in Spanish? Train your skills in writing numbers with the following exercise:

Numerals
Numbers trainer

 

Verbs

Do you know how to conjugate regular and irregular Spanish verbs yet? Train your skills in Spanish verb conjugation:

Complete verb tenses Random verb forms
Verb tense trainer Random verb form trainer