Reflections on School Selection

Apr 30 2025

The exam is now just a few days away.

While students must be feeling nervous, it is often the parents who carry an even heavier burden in their hearts.
The desire to provide even slightly better opportunities for your child, and the deep love that drives you to do your best for them, makes this time feel especially heavy and sensitive.

Yet, our children do not always move exactly according to our hopes.
Perhaps that is simply part of the natural process of growing up.

This message is shared with the hope that you can read it with a light heart.
For now, the most important thing is for your child to perform well in the exam.
School choices can be adjusted after the exam is over.

There is no need to burden your heart with excessive worries right now.
It will never be too late to calmly reconsider school selections after the exam is completed.

These ideas are, in fact, simply common sense.
When it is someone else’s situation, it seems clear and rational.
However, when it becomes our own situation, it is natural for emotions to cloud our judgement.

Especially nowadays, with the rapid development of social media,
it is easy to encounter countless personal experiences being generalised hastily.
Reading such case-by-case stories can easily shake our confidence.

But remember —
Feeling anxious or uncertain is a natural human response.
It does not mean you are wrong or weak.
It simply means you care deeply.

Now, more than anything else,
the greatest gift you can give your child is your calm support and warm encouragement,
so they can approach the exam with peace of mind and do their best.

1. Background: Why Prediction is Difficult

Analysis of TTC data shows that
while some students consistently maintain their ranking regardless of difficulty,
others experience significant fluctuations depending on the exam.
Therefore, the reliability of predictions is:
Higher for students whose performance remains consistent,
Lower for students whose performance is unstable.
Exam results can vary due to many external factors.
This is similar to sports or musical competitions.
For example, the FIFA-ranked No. 1 team does not always win the World Cup.

2. Structure of the Selective High School Test

System Structure
• The Selective High School Test offers places strictly based on ranking within a set number of available spots.
• It is not about absolute scores but relative performance.
• Even if a student scores 99, if more than ten students score 100 for ten available places, the student may not receive an offer.
Why was this system created?
• The Selective High School system was developed by the NSW Department of Education.
• As public schools, Selective High Schools cannot leave places unfilled, unlike private or catchment-based local schools.
• Therefore, to ensure that all places are filled, the system operates through:

– Three stages of selection (Initial Offer → Reserve → Late Offer),
– Reserve lists, and
– Selective Transfers for Years 7–10 to fill mid-year vacancies.

• The selection and placement process is detailed and systematic because all available spots must be filled each year.

3. How School Preference order is commonly determined in the market

Two main criteria are widely used:

1. Cut-off Score System
• Schools are selected based on past published cut-off scores.
• However, these cut-off scores represent the last reserve offer and may not perfectly reflect the actual minimum admission level.

2. Sydney Morning Herald (SMH) HSC Rankings
• Schools are ranked based on HSC performance results published by SMH.
• While useful as a general reference, these rankings are not a perfect indicator of a school’s overall quality and are influenced by our natural trust in numbers.
Why is school preference determined this way?

• Most parents and students tend to apply to higher-ranking schools as their first preference.
• Reflecting market trends, using cut-off scores and HSC rankings provides a more realistic approach to setting school choices.

4. Prediction Models and Their Limitations

Model A: TTC Score Compared with Cut-off
• Individual TTC scores are compared to past cut-off scores to predict likely outcomes.
• When the sample size is small, it is difficult to use group averages or rankings, so simple direct comparisons are typically used.
• It is quick and intuitive but does not fully account for variations in exam difficulty or year-to-year changes.
Model B: TTC Score Plus Ranking Percentage
• This method considers both the individual score and the student’s percentile rank within the group.
• It is more reliable when the sample size is large, but less effective with smaller groups.
Model C: Hybrid Model
• A balanced approach that considers both scores and ranking.
• To reduce prediction errors, rather than suggesting only one school, a range of possible schools is recommended.
• This allows students and parents to build more flexible and realistic strategies.

5. Additional Factors Complicating Prediction

Equity Model Implementation
The Department of Education has not disclosed the detailed standards for applying the Equity Model, making predictions difficult.
Reserve System
Final offers can change based on parental decisions and movement between schools.
Changes from 2025
The exam has shifted to a new structure spread over three days, making outcomes even harder to predict.

6. Conclusion

Students with consistent performance can be predicted with a relatively high degree of reliability based on past data.
For students with variable performance, discrepancies between predicted and actual outcomes are more common.
School selection is not a matter of perfect prediction but of making the best decision based on available information and trends.