I found this information online.
The protein needs of preschool children can be easily meet by giving them several small snacks and meals throughout the day from a variety of plant foods. According to the National Academy of Sciences, total caloric intake and the RDA of protein for young children is as follows...
Ages 1 to 3 - 1300 calories and 16 grams protein
Ages 4 to 6 - 1800 calories and 24 grams protein
Ages 7 to 10 - 2000 calories and 28 grams protein
For 3 g of protein you can get something like the CLif Zbars (made for kids), or supplement with the adult versions and offer half a bar as a snack or treat for the lunch or after school snack/treat. CLif brand makes one called a Builder bar and has about 20 g of protein but they are large. Builder bars taste like a candy bar. I LOVE the chocolate mint ones!!
How about cheese sticks? Will he eat those? Most string cheese looks like about 6g. Colby cheese sticks looks about 5.
Iron guides I see are as follows:
◦Children ages 7 to 12 months need 11 mg, 1 to 3 years 7mg, 4 to 8 years 10mg, 9-13 years 8mg, 14 to 18 years 11 mg (for boys), 15 mg (for girls).
Total and Raisin Bran cereals come up on many lists as Iron Friendly that I see. I assume they are fortified as many breakfast cereals are. Others are green leafy veggies, and things I personally find ishy like liver! Yuck! LOL
At a daycare USDA Food Program Training I did a few years back (I am a provider of 14 years), a "tip" they had to increase iron intake for kids in an easy way (well for anyone) was to add sesame seeds to alot of foods. I do this with my daycare kids. I have them in a shaker and they can add them to anything they want. For my family, we add them to salads, on top of steaks and chicken, in anything we saute or stir fry (alot of veggies and meat dishes. Its like adding salt or pepper...just a sprinkle on top of most foods. My kids (2 and up really) enjoy the operation of using the shaker really and "decorating" their food.
For older kids, when I first started this, I had to show them that they are whats on top of a hamburger bun from the fast food joints. That helped convince them!