Should I encourage foreign students to adopt local handwriting customs? I am an American teaching in a US university, and I've noticed that many foreign students come with their own handwriting customs for writing English. In particular I've noticed that Indian students often write the letter 'x' so that it (to me, anyway, and probably to many Americans) resembles an 'n', and makes their work (very slightly) harder to read. (Another example: a Croatian friend of mine wrote his 'q' so that it looked like 'g' to me.)

Should I encourage them to write in an American way? I am especially interested in hearing from foreigners and whether they would have appreciated this. On the one hand I don't want to presume that my culture is superior to others; on the other, they have chosen to study in the US and I would like to help them communicate their ideas with as few obstacles as possible.

Does the answer depend on circumstances (e.g. whether the student is an undergraduate or graduate, whether the student has teaching responsibilities, and where the student aims to work after graduation)?
In ordinary text, this might help a little but probably doesn't matter much, since there's plenty of redundancy to aid in understanding.  However, it can make a big difference for equations.

If the students are in a math-intensive field, I would definitely point this out, but in a broader context.  When I teach beginning American undergraduates in mathematics, I offer them handwriting advice for equations: make sure t doesn't look like +, z doesn't look like 2, the letter l doesn't look like the number 1, etc.  Furthermore, mathematics students have to learn how to write all sorts of potentially unfamiliar symbols as they progress in their studies (aleph, Weierstrass P, fraktur letters for Lie theory, etc.).  If you are working on a calculation on a whiteboard with someone, it's a real issue if they can't easily and reliably parse your equations, so just about every mathematician has put at least a little thought into this.

From this perspective, I wouldn't tell people "You're in America now and have to write like the Americans", but rather "Writing equations clearly is something everyone has to deal with.  Here are some issues you may need to adapt to, some of which are generic and others of which are specific to your background."