Great lesson on the use of por and para. Ample examples illustrate the rules for their application. A quiz follows the lesson to test the student's mastery of por and para.

This site is a lesson on possessive adjectives.An adequate number of examples enhance the explanation. The student can test his mastery of the grammar principle with a short quiz at the end of the lesson.

This explanation of possessive pronouns in Spanish offers examples that illustrate their use. Students may test their mastery of this concept with a quiz that follows the lesson.

This explanation of the present progressive tense includes stem-changing present participles and those that involve spelling changes. Examples illustrate this grammar principle and a test assesses student mastery of the content.

Great lesson for identifying words and phrases that indicate which past tense to use, preterite or imperfect. Though not meant to be a comprehensive lesson on the application of these two past tenses, the two lists of time expressions provide students with a quick and practical start to using the preterite and imperfect tenses.A quiz at the end of the lesson tests the student's mastery of this grammar principle.

This site is an introduction to verbs that change meaning according to which past tense is applied, preterite or imperfect. Examples in English and Spanish illustrate the change of meaning. A quiz at the end of the lesson tests the student's mastery of this grammar principle.

Comprehensive review of the preterite and imperfect past tenses. Includes regular, irregular, and stem-changing conjugations. Rules for usage and time expressions in Spanish are listed. A quiz at the end of the lesson tests the student's mastery of the preterite and imperfect tenses.

This site is an explanation of prepositional pronouns with a list of prepositions that only take subject pronouns. Great lesson for understanding prepositional pronouns. Students may check test their mastery of this principle with a quiz that follows the lesson.

An excellent review of relative pronouns and adjectives in Spanish. Ample examples in Spanish and English illustrate their usage. Students may test their mastery of this principle with a quiz that follows the lesson.

Fantastic explanation of relative pronouns with an introduction to using the Spanish relative pronoun "que." Ample examples in Spanish and English illustrate the use of "que," as a relative pronoun. Students may test their understanding of the relative pronoun "que," with a quiz that follows the lesson.

An excellent introduction to using the Spanish relative pronoun "quien," that contrasts its use with the pronoun "que," Ample examples in Spanish and English illustrate this principle. Students may test their understanding of the relative pronouns "quien," and "que," with a quiz that follows the lesson.

After a brief review of what verbs and verb infinites are, this site offers a comprehensive explanation of subject pronouns. A great comparison of Spanish subject pronouns to English subject pronouns. Differences between second person pronouns tu, usted, ustedes and vosotros are explained. Great lesson for understanding subject pronouns.

Great explanation of the subjunctive mood used to express ignorance or doubt and contrasted to contradictory applications in the indicative. Ample examples illustrate the difference between these two moods. A useful list of expressions that indicate ignorance or doubt is provided. A quiz at the end of the lesson tests the student's comprehension of the present subjunctive utilized to demonstrate ignorance or doubt.

Great explanation of how to conjugate the six irregular verbs in the present subjunctive: dar, estar, haber, ir, saber, and ser. A quiz at the end of the lesson tests the student's mastery of irregular conjugations in the present subjunctive.

Comprehensive lesson on how to conjugate verbs in the present subjunctive. Regular and stem-changing verbs are presented in this explanation. A quiz at the end of the lesson tests the student's mastery of verb conjugations in the present subjunctive.

Fantastic explanation of spelling changes in the Spanish language and their effect upon conjugations in the present subjunctive. Verb infinitives that end in -car, -gar, and -zar are among those that are considered. A quiz at the end of the lesson tests the student's mastery of verb conjugations in the present subjunctive that are altered by orthographical changes.

This Spanish tutorial on special uses of the definite article and exceptions to the rules for its normal usage features examples that illustrate its application to countries, titles and other special situations. Students test their mastery of this grammar principle with a quiz that follows the lesson.

Written for the U.S. Center of Military History, this article explores the military lessons learned by the deployment of the American Expeditionary Forces in World War I. Read about the problems involved in training a fighting force for a major conflict.

This article highlights activities for elementary students that model icebergs and develop an informal understanding of the concepts of buoyancy and density. Suggestions for inquiry-based activities are included.

This article highlights hands-on and inquiry-based science lessons that teach about the water cycle and provides lessons that integrate literacy skills with the science investigations.