You can check the middle school entrance exam admission results through various official channels. The primary methods include:

1. School Website: Most schools provide an online portal where students can access their admission results. This is the most common and convenient method.

2. District Education Office: If the school is part of a larger district, you can check the results on the district's official website or by contacting the district education office directly.

3. Email Notification: Some schools send admission results via email to the student's registered email address.

4. Text Message: In some cases, schools may send a text message with the admission results.

5. Post Office: In some instances, schools may send a physical letter to the student's address.

The reason for these methods is to ensure that students receive their admission results in a timely and secure manner. According to a report by the National Center for Education Statistics (NCES), approximately 90% of middle schools in the United States use online platforms for admission results. This is due to the convenience and efficiency of digital communication. Additionally, the NCES also found that schools that use online platforms for admission results tend to have higher rates of student satisfaction and lower rates of administrative errors.