A helmet can include a helmet body formed of a foam energy-absorbing material in which the helmet body includes inner and outer opposing surfaces. A plurality of lower slots can be formed completely through the helmet body and can be open at a lower edge of the helmet body. A plurality of upper slots can be formed completely through the helmet body and be open at a top portion of the helmet body to form a star shape. An S-shaped panel of the helmet body can include an undulating form from the alternating and overlapping positions of the plurality of lower slots and the plurality of upper slots. A reinforcing halo can be disposed within the helmet body to reinforce areas of weakness in the helmet body resulting from the plurality of lower slots and the plurality of upper slots.