Set up a meeting with one or both of a student's parents in a pleasant, neutral place with adequate seating and lighting. You may wish to meet in a classroom or office.
Create a measurement form with multiple-choice questions. Questions should address how often students speak to parents about specific issues, such as, "How often do you and your child discuss school activities?" The choices would be never, once a month, several times a month, once a week or several times a week." Questions should also deal with how often parents help with homework, impose restrictions or talk about life issues such as friendship troubles.
Meet with the parents and ask them to fill out the questionnaire. You can make the questions written or ask them orally and listen to their answers.
Look at your records to determine how often the parents attend school events, parent-teacher meetings or speak to you specifically about a student's needs or problems. If you do not have records, ask the parent these questions.
Assign a value for each answer. For example, "never" might have a value of 0, "once a month" a value of 1 and "several times a month" a value of 2. Add one point for each increase in frequency.
Create a score of each answer. Add all of these scores together and compare them to the scores of other parents. You may wish to compare them to the maximum possible score to see how close parents are to the ideal. For example, if the maximum score is 100 and a parent scores 90, his involvement is high. If he scores 30, his involvement is low.