Make classroom teachers happy, reinforce phonics and handwriting, and practice speech all at the same time.
Younger children will just enjoy identifying the pictures and working on clear initial /h/ sounds while letting you fill in the letter "h" for them. Slightly older students can work on their handwriting and fine motor skills by writing in the letter themselves.
As always, you can practice these words in isolation, in repetitions of two or three, with carrier phrases, or in short sentences. If you're sending the sheet home for homework, write in extra directions if you want the parents to practice at a particular level.
This worksheet is modeled after The Missing Vowel worksheets included in the Simple Vowels Speech Kit.