What methods can a teacher use to differentiate to a new group of students in a class?

I do not fully understand the question, but I guess this is about what interesting intro I can use - I usually start talking to students, asking names and asking them to tell their Birthdays, what they like and why they are here 

 

• Readiness to learn
• Learning needs
• Interest

collaborative learning has many well-documented benefits such as enabling shy students to participate more confidently in class, but it’s also a useful differentiation method. Small, mixed-ability groups allow lower achievers to take advantage of peer support whilst higher achievers gain the opportunity to organize and voice their thoughts for the benefit of the whole group (known as peer modeling). Grouping also allows roles to be allocated within the team which caters for each member’s skill set and learning needs.

Introduction one by one and try to know their interest and their level of understanding

A teacher will ask their names and do a nice introduction

If I was a teacher I would have my old students explain to the new group in addition I would rephrase also what old students explains to new group. And then have new group explain back what they understood to whole class ....... With above we will have following benefits 1. Old students can prove they understood along with get their confidence increased..... 2. New students can understood as well as may be can come with some new ideas which can further the understanding in a better way.... 3. Group discussion will lead to team spirit 4. Healthy discussion will make feel everyone part of team..... 5. When team is united and happy, profit in terms of cash, socially, innovation and other ways are always rocket high