Conjure Tiny Elemental

You summon a tiny elemental that orbits above your head for one minute.  As a bonus action, or part of the action to cast the spell, one or more summoned  tiny elementals make a ranged spell attack (using your ranged spell attack modifier) doing 1d4+1 damage on a successful hit.   After its second ranged attack (or 1 minute elapses, whichever is first) the tiny elemental winks out of existence.  An elemental can be dismissed as a free action.   You may have a maximum of 2 elementals summoned at the same time (all of which disappear if the caster loses concentration.)  

The type of elemental (earth, air, water, fire) determines the damage type of the attack (bludgeoning, thunder, cold, or fire respectively) and is chosen when the cantrip is learned.
[GM Option 1: The type of elemental summoned can be changed during a short rest.]
[GM Option 2: Sorcerers can spend a sorcery point to choose a different elemental type]
[GM Option 3: The type of elemental summoned is chosen freely each time the cantrip is cast.]

The spell increases in power as the caster increases levels.
5th level: You may have a maximum of 3 elementals, and they each may make 3 attacks before disappearing.   (3 attacks at 1d4+1)
11th level: The damage of the elementals' attacks increase to 1d6+1 
17th level: The damage of the elementals' attacks increase to 2d6+1

[GM Notes: If a player wants to further pursue the idea of actually summoning elementals, they can be given an AC of 10 and HP of 1, which make them eligible as targets, but also vulnerable to enemy area attacks.]

Notes: This spell was designed for my son who wanted to be able to summon elementals, but there were no low-level summoning spells so this was designed to give him the taste of summoning at low levels.  The power level is fairly well balanced, but I do not let him "charge up" several elementals before combat starts.  If that becomes a problem, a GM could set the length of the spell to only 3 or 4 rounds.