Blooms Taxonomy is a framework that helps educators to design and assess learning outcomes that promote higher order thinking skills. It is a hierarchical model that categorizes thinking skills into six levels, ranging from lower order thinking skills (LOTS) to higher order thinking skills (HOTS). The six levels of Blooms Taxonomy are:

1. Remembering: recalling information from memory
2. Understanding: comprehending the meaning of information
3. Applying: using information in a new situation or context
4. Analyzing: breaking down information into parts and examining relationships
5. Evaluating: making judgments about the value or quality of information
6. Creating: generating new ideas, products, or solutions

To demonstrate high order thinking in assessment task creating across curricula from Year 3 - Year 10, educators can use the following strategies:

1. Start with the end in mind: Begin by identifying the learning outcomes that you want students to achieve. This will help you to design assessment tasks that align with the desired learning outcomes.

2. Use a variety of assessment formats: Use a range of assessment formats, such as essays, projects, presentations, and exams, to assess different types of thinking skills.

3. Scaffold the learning: Provide students with opportunities to practice and develop their thinking skills through scaffolded activities and tasks. This will help them to build their confidence and competence in using higher order thinking skills.

4. Use real-world scenarios: Use real-world scenarios and problems to help students apply their thinking skills in authentic contexts. This will help them to see the relevance and importance of the skills they are learning.

5. Provide feedback: Provide students with feedback on their thinking skills, highlighting areas of strength and areas for improvement. This will help them to develop their skills further and become more confident in using them.

6. Encourage reflection: Encourage students to reflect on their thinking processes and the strategies they used to solve problems. This will help them to become more metacognitive and develop their ability to think critically about their own thinking.

By using these strategies, educators can design assessment tasks that promote higher order thinking skills across curricula from Year 3 - Year 10. This will help students to develop the skills they need to succeed in the 21st century workforce and become lifelong learners.