Those are looking good, tell your son I am impressed.
I just planted some seeds with my children this past weekend.
I much prefer direct sowing just because of the ease of it but the seedlings do you give you that head start
They all have their own vegetable bed in the garden and were excited to pick out seeds and start planting so I helped them start some seedlings.
Beware, if you let your children pick out seeds you will be eating purple and orange cauliflower, rainbow(who knew they came in so many colors?) colored carrots, purple radishes,blue mashed potatoes and red french fries. Oh and lets not forget the pointy starry looking broccoli and all the funny looking squash.
Its all good though, it gets them interested in gardening and makes them eat their veggies.