Recommend me a "writing icing" for cookies

Title pretty much explains it. I need a brand of icing that comes in a few colors (blue being one), comes already in a tube for easy use in writing, and is pliant enough to be used by a 9- or 10-yr-old, but still hold together, so you can write legibly.

Reviews online are so mixed, it’s hard to pick-- there are some universally despised, but none that are getting enough praise to dismiss the 1-star reviews as just complainers, a bad batch, or a long time ago (I even spot-checked, and people leaving 1-star reviews don’t generally leave a lot of poor reviews.

The best one by the reviews is made by Wilton, but Wilton’s palette is limited-- and it doesn’t seem to have blue. I know Wilton does make generally good products, though.

Buying for work, so don’t have to worry about price.

Kids will be writing Hebrew letters, although not required to write more than one (well, technically not required to write any, but they have to write at least one to get the cookie). So, not demanding in volume, but asks a bit of the kids. Not for a grade, not an exam. Just a fun activity for a holiday.

Anyway, if you have had a good experience with an icing, or a particularly bad one, PLEASE share, and name the brand. Also, give me a time-frame-- if it was 5 years ago, and someone else says it was great 6 months ago, maybe it’s improved.

I know there are some other threads about icing cookies, but they are old enough that I feel I really need a fresh one.

I’m going to experiment before, but if you have any advice, such as “lay icing on the whole thing for a writing surface”, I welcome that.